Upgrade to NBB 5

.NET 5 upgrade

Update TargetFramework in *.csproj files to net5.0 (for both netcoreapp and netstandard projects)
Update Microsoft.Extensions.* references to version 5.0.0
Microsoft.CSharp package version 4.7.0
Remove <LangVersion><LangVersion> from csproj
Update Dockerfile to use the following images
- mcr.microsoft.com/dotnet/aspnet:5.0-buster-slim
- mcr.microsoft.com/dotnet/sdk:5.0-buster-slim
- mcr.microsoft.com/dotnet/runtime:5.0-buster-slim

Upgrade NNB packages version 5.x.x (latest)
Renamed/removed packages
- NBB.Messaging.DataContracts was merged with NBB.Messaging.Abstractions
- NBB.Resiliency was removed
  - reference can be deleted, messaging policies are included in NBB.Messaging.Abstractions
  - services.UseResiliency() can be deleted
- NBB.Application.DataContracts is deprecated
  - Transitive references to NBB.Application.DataContracts 4.x should be fixed with direct references to NBB.Application.DataContracts 5.x
  - MediatorUoWDecorator was moved to NBB.Application.MediatR
Relocated packages - some packages were moved to NBB.Extras repo and have different versioning (v4.x)
- NBB.Exporter.* uses NBB.Extras versioning
- NBB.Tools.AutomapperExtensions uses NBB.Extras versioning

IMessageBusPublisher signature changed
- TopicName and EnvelopeCustomizer moved to "MessagingPublisherOptions"
- CancellationToken parameter moved last
Messaging Host Middleware signature changed
- The "Invoke" method handles a MessagingContext instead of a MessagingEnvelope
- The "MessagingEnvelope" is a field in the MessagingContext
"services.AddNatsMessaging()" will be replaced by "services.AddMessageBus().AddNatsTransport(Configuration)"
- to support compatibility with NBB4 topics add "UseTopicResolutionBackwardCompatibility(Configuration)" from the package "NBB.Messaging.BackwardCompatibility"
"services.AddMessagingHost()" now uses an inner host builder "services.AddMessagingHost(hostBuilder => hostBuilder.Configure(...))"

Remove "AddProcessManagerDefinition(...)", "AddProcessManagerRuntime(...)", "AddNotificationHandlers", TimeoutOccuredHandler registratin
Replace all with "AddProcessManager(typeof(SomePM).Assembly)"
Remove classes for ProcessManagerNotificationHandler, TimeoutOccuredHanlder

Interfaces like ICommand, IQuery, IEvent no longer exist
Base classes like Command, Query<T>, Event no longer exist
For generic command handling code we can use IRequest instead of Command/ICommand
For generic event handling code we can use INotification or object instead of Event/IEvent
Queries should extend IRequest<T> instead of Query<T>
Commands, Events and Queries can be rewritten as C# 9.0 "records" (immutable reference types)

https://docs.microsoft.com/en-us/ef/core/what-is-new/ef-core-3.x/breaking-changes
DBQuery should be replaced with DBSet (use .HasNoKey if required)
IQueryTypeConfiguration<TQuery> should be replaced by IEntityTypeConfiguration<TEntity>
ModelBuilder.Query<>() should be replaced with ModelBuilder.Entity<>().HasNoKey()
DBSet.FromSql should be repladed with FromSqlRaw
- Make sure the entity is configured with HasNoKey()
- Make sure no linq is used on the query such as FirstOrDefaultAsync(). Replace with ToListAsync().FirstOrDefault()
ValueGenarator.NextAsync returns ValueTask instead of task
ExecuteSqlCommand should be replaced with ExecuteSqlRaw (similarly for async version)
IProperty.Relational().TableName -> IProperty.GetTableName()
Microsoft.Data.SqlClient is used instead of System.Data.SqlClient
Concurrent DB operations throw exceptions (cannot have multiple DB tasks in parallel for the same DBContext)
Remove the call to .AddEntityFrameworkSqlServer() it is not necessary unless using a custom service provider
Non-null reference navigations are not overwritten by queries
- Do not initialize reference navigation properties https://docs.microsoft.com/en-us/ef/core/what-is-new/ef-core-5.0/breaking-changes#nonnullreferences
- Initialized collections still work.
For queries with multiple colection "includes" use AsSplitQuery()
- PropertyBuilder.UseSqlServerIdentityColumn() -> PropertyBuilder.UseIdentityColumn()

ValidationContext should be replaced with ValidationContext<T>
CascadeMode.StopOnFirstFailure should be replaced with CascadeMode.Stop
Constructor custom message should be replaced with override string GetDefaultMessageTemplate()
Replace RuleFor(...).SetcollectionValidator(...) with RuleForEach(...).SetValidator(...)
Replace ValidatorOptions.LanguageManager with ValidatorOptions.Global.LanguageManager

IRequestHandler / Handle method returns Task<Unit> now
- use Unit.Value or Unit.Task as return value
Make sure that the package "MediatR.Extensions.Microsoft.DependencyInjection" has the same version as "MediatR"

[MyProject].PublishedLanguage
- remove Newtonsoft.Json package reference
Replace NBBProcessManagerRuntime build variable with NBBPackagesVersion
IConfiguration does not contain GetValue<>
- add Microsoft.Extensions.Configuration.Binder package reference
AddScoppedContravariant should support multiple type arguments like IRequest<T, Unit>
Replace IHostingEnvironment with IWebHostEnvironment
Replace packages like "Microsoft.Aspnet*.Abstractions" with <FrameworkReference Include="Microsoft.AspNetCore.App" />
Automapper for positional records: does not work with "ForMember" mappings. Either use "ForCtorParam" or use nominal records.
Remove DTO SchemaFilter for swagger for metadata after replacing Command/Query with IRequest