[3.0] Add gen MethodDescriptor valid, avoid strange situations

[EarthChen]

What is the purpose of the change

• Add gen MethodDescriptor valid, avoid strange situations

Brief changelog

Verifying this change

Checklist

• Make sure there is a GitHub_issue field for the change (usually before you start working on it). Trivial changes like typos do not require a GitHub issue. Your pull request should address just this issue, without pulling in other changes - one PR resolves one issue.
• Each commit in the pull request should have a meaningful subject line and body.
• Write a pull request description that is detailed enough to understand what the pull request does, how, and why.
• Check if is necessary to patch to Dubbo 3 if you are work on Dubbo 2.7
• Write necessary unit-test to verify your logic correction, more mock a little better when cross module dependency exist. If the new feature or significant change is committed, please remember to add sample in dubbo samples project.
• Add some description to dubbo-website project if you are requesting to add a feature.
• GitHub Actions works fine on your own branch.
• If this contribution is large, please follow the Software Donation Guide.

[codecov-commenter]

Codecov Report

Merging #8651 (c51a003) into 3.0 (067dba3) will increase coverage by 0.21%.
The diff coverage is 84.93%.

@@             Coverage Diff              @@
##                3.0    #8651      +/-   ##
============================================
+ Coverage     63.28%   63.49%   +0.21%     
- Complexity      311      312       +1     
============================================
  Files          1121     1121              
  Lines         46915    46975      +60     
  Branches       7067     7093      +26     
============================================
+ Hits          29690    29828     +138     
+ Misses        13932    13850      -82     
- Partials       3293     3297       +4     

Impacted Files	Coverage Δ
...a/org/apache/dubbo/rpc/model/MethodDescriptor.java	84.37% <84.93%> (+10.84%)	⬆️
.../remoting/transport/netty4/NettyServerHandler.java	62.79% <0.00%> (-9.31%)	⬇️
...e/dubbo/remoting/transport/netty/NettyChannel.java	55.68% <0.00%> (-3.41%)	⬇️
...apache/dubbo/common/extension/ExtensionLoader.java	79.41% <0.00%> (ø)
...pc/protocol/tri/TripleHttp2FrameServerHandler.java	40.36% <0.00%> (+0.91%)	⬆️
...e/dubbo/rpc/protocol/tri/AbstractServerStream.java	55.00% <0.00%> (+1.00%)	⬆️
...pache/dubbo/remoting/transport/AbstractServer.java	62.85% <0.00%> (+1.42%)	⬆️
.../apache/dubbo/rpc/protocol/tri/AbstractStream.java	44.30% <0.00%> (+1.89%)	⬆️
.../apache/dubbo/remoting/transport/AbstractPeer.java	65.21% <0.00%> (+2.17%)	⬆️
...he/dubbo/remoting/transport/netty/NettyServer.java	73.68% <0.00%> (+3.50%)	⬆️
... and 8 more

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[guohao]

LGTM