Update-Snippets fails with Sequence contains no matching element

[pakrym]

    
      Replaced Snippet:CustomChainedTokenCredential in C:\azure-sdk-for-net\sdk\identity\Azure.Identity\README.md
System.AggregateException: One or more errors occurred. (Sequence contains no matching element) ---> System.InvalidOperationException: Sequence contains no matching element
   at System.Linq.Enumerable.First[TSource](IEnumerable`1 source, Func`2 predicate)
   at SnippetGenerator.DirectoryProcessor.GetAllSnippets(SyntaxTree syntaxTree) in C:\azure-sdk-for-net\eng\SnippetGenerator\DirectoryProcessor.cs:line 225
   at SnippetGenerator.DirectoryProcessor.GetSnippetsInDirectory(String baseDirectory) in C:\azure-sdk-for-net\eng\SnippetGenerator\DirectoryProcessor.cs:line 211
   at SnippetGenerator.DirectoryProcessor.DiscoverSnippets() in C:\azure-sdk-for-net\eng\SnippetGenerator\DirectoryProcessor.cs:line 90
   at System.Lazy`1.ViaFactory(LazyThreadSafetyMode mode)
   at System.Lazy`1.ExecutionAndPublication(LazyHelper executionAndPublication, Boolean useDefaultConstructor)
   at System.Lazy`1.CreateValue()
   at SnippetGenerator.DirectoryProcessor.<>c__DisplayClass8_0.<Process>g__SnippetProvider|0(String s) in C:\azure-sdk-for-net\eng\SnippetGenerator\DirectoryProcessor.cs:line 49
   at SnippetGenerator.MarkdownProcessor.<>c__DisplayClass2_0.<Process>b__0(Match match) in C:\azure-sdk-for-net\eng\SnippetGenerator\MarkdownProcessor.cs:line 22
   at System.Text.RegularExpressions.Regex.Replace(MatchEvaluator evaluator, Regex regex, String input, Int32 count, Int32 startat)
   at System.Text.RegularExpressions.Regex.Replace(String input, MatchEvaluator evaluator, Int32 count, Int32 startat)
   at System.Text.RegularExpressions.Regex.Replace(String input, MatchEvaluator evaluator)
   at SnippetGenerator.MarkdownProcessor.Process(String markdown, Func`2 snippetProvider) in C:\azure-sdk-for-net\eng\SnippetGenerator\MarkdownProcessor.cs:line 17
   at SnippetGenerator.DirectoryProcessor.Process() in C:\azure-sdk-for-net\eng\SnippetGenerator\DirectoryProcessor.cs:line 71
   at SnippetGenerator.Program.<>c.<OnExecuteAsync>b__4_0(String sdkDir) in C:\azure-sdk-for-net\eng\SnippetGenerator\Program.cs:line 24
   at System.Threading.Tasks.Parallel.<>c__DisplayClass32_0`2.<ForEachWorker>b__0(Int32 i)
   at System.Threading.Tasks.Parallel.<>c__DisplayClass19_0`1.<ForWorker>b__1(RangeWorker& currentWorker, Int32 timeout, Boolean& replicationDelegateYieldedBeforeCompletion)
--- End of stack trace from previous location where exception was thrown ---
   at System.Threading.Tasks.Parallel.<>c__DisplayClass19_0`1.<ForWorker>b__1(RangeWorker& currentWorker, Int32 timeout, Boolean& replicationDelegateYieldedBeforeCompletion)
   at System.Threading.Tasks.TaskReplicator.Replica`1.ExecuteAction(Boolean& yieldedBeforeCompletion)
   at System.Threading.Tasks.TaskReplicator.Replica.Execute()
   --- End of inner exception stack trace ---
   at System.Threading.Tasks.TaskReplicator.Run[TState](ReplicatableUserAction`1 action, ParallelOptions options, Boolean stopOnFirstFailure)
   at System.Threading.Tasks.Parallel.ForWorker[TLocal](Int32 fromInclusive, Int32 toExclusive, ParallelOptions parallelOptions, Action`1 body, Action`2 bodyWithState, Func`4 bodyWithLocal, Func`1 localInit, Action`1 localFinally)
--- End of stack trace from previous location where exception was thrown ---
   at System.Threading.Tasks.Parallel.ThrowSingleCancellationExceptionOrOtherException(ICollection exceptions, CancellationToken cancelToken, Exception otherException)
   at System.Threading.Tasks.Parallel.ForWorker[TLocal](Int32 fromInclusive, Int32 toExclusive, ParallelOptions parallelOptions, Action`1 body, Action`2 bodyWithState, Func`4 bodyWithLocal, Func`1 localInit, Action`1 localFinally)
   at System.Threading.Tasks.Parallel.ForEachWorker[TSource,TLocal](TSource[] array, ParallelOptions parallelOptions, Action`1 body, Action`2 bodyWithState, Action`3 bodyWithStateAndIndex, Func`4 bodyWithStateAndLocal, Func`5 bodyWithEverything, Func`1 localInit, Action`1 localFinally)
   at System.Threading.Tasks.Parallel.ForEachWorker[TSource,TLocal](IEnumerable`1 source, ParallelOptions parallelOption--- End of stack trace from previous location where exception was thrown ---
   at McMaster.Extensions.CommandLineUtils.Conventions.ExecuteMethodConvention.Invoke(MethodInfo method, Object instance, Object[] arguments)
   at McMaster.Extensions.CommandLineUtils.Conventions.ExecuteMethodConvention.OnExecute(ConventionContext context)
   at McMaster.Extensions.CommandLineUtils.Conventions.ExecuteMethodConvention.<>c__DisplayClass0_0.<<Apply>b__0>d.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at McMaster.Extensions.CommandLineUtils.CommandLineApplication.<>c__DisplayClass142_0.<OnExecute>b__0()
   at McMaster.Extensions.CommandLineUtils.CommandLineApplication.Execute[TApp](IConsole console, String[] args)
   at SnippetGenerator.Program.Main(String[] args) in C:\azure-sdk-for-net\eng\SnippetGenerator\Program.cs:line 38
---> (Inner Exception #0) System.InvalidOperationException: Sequence contains no matching element
   at System.Linq.Enumerable.First[TSource](IEnumerable`1 source, Func`2 predicate)
   at SnippetGenerator.DirectoryProcessor.GetAllSnippets(SyntaxTree syntaxTree) in C:\azure-sdk-for-net\eng\SnippetGenerator\DirectoryProcessor.cs:line 225
   at SnippetGenerator.DirectoryProcessor.GetSnippetsInDirectory(String baseDirectory) in C:\azure-sdk-for-net\eng\SnippetGenerator\DirectoryProcessor.cs:line 211
ssor.cs:line 90
   at System.Lazy`1.ViaFactory(LazyThreadSafetyMode mode)
   at System.Lazy`1.ExecutionAndPublication(LazyHelper executionAndPublication, Boolean useDefaultConstructor)
   at System.Lazy`1.CreateValue()
   at SnippetGenerator.DirectoryProcessor.<>c__DisplayClass8_0.<Process>g__SnippetProvider|0(String s) in C:\azure-sdk-for-net\eng\SnippetGenerator\DirectoryProcessor.cs:line 49
   at SnippetGenerator.MarkdownProcessor.<>c__DisplayClass2_0.<Process>b__0(Match match) in C:\azure-sdk-for-net\eng\SnippetGenerator\MarkdownProcessor.cs:line 22
   at System.Text.RegularExpressions.Regex.Replace(MatchEvaluator evaluator, Regex regex, String input, Int32 count, Int32 startat)
   at System.Text.RegularExpressions.Regex.Replace(String input, MatchEvaluator evaluator, Int32 count, Int32 startat)
   at System.Text.RegularExpressions.Regex.Replace(String input, MatchEvaluator evaluator)
   at SnippetGenerator.MarkdownProcessor.Process(String markdown, Func`2 snippetProvider) in C:\azure-sdk-for-net\eng\SnippetGenerator\MarkdownProcessor.cs:line 17
   at SnippetGenerator.DirectoryProcessor.Process() in C:\azure-sdk-for-net\eng\SnippetGenerator\DirectoryProcessor.cs:line 71
   at SnippetGenerator.Program.<>c.<OnExecuteAsync>b__4_0(String sdkDir) in C:\azure-sdk-for-net\eng\SnippetGenerator\Program.cs:line 24
   at System.Threading.Tasks.Parallel.<>c__DisplayClass32_0`2.<ForEachWorker>b__0(Int32 i)
   at System.Threading.Tasks.Parallel.<>c__DisplayClass19_0`1.<ForWorker>b__1(RangeWorker& currentWorker, Int32 timeout, Boolean& replicationDelegateYieldedBeforeCompletion)
   at System.Threading.Tasks.Parallel.<>c__DisplayClass19_0`1.<ForWorker>b__1(RangeWorker& currentWorker, Int32 timeout, Boolean& replicationDelegateYieldedBeforeCompletion)
   at System.Threading.Tasks.TaskReplicator.Replica`1.ExecuteAction(Boolean& yieldedBeforeCompletion)
   at System.Threading.Tasks.TaskReplicator.Replica.Execute()<---