[3.0] Add unit test for TraceFilter

[icankeep]

What is the purpose of the change

issue: #7876
pick from master 38919254

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 #7898 (c54e4a5) into 3.0 (537755b) will increase coverage by 0.08%.
The diff coverage is n/a.

@@             Coverage Diff              @@
##                3.0    #7898      +/-   ##
============================================
+ Coverage     58.81%   58.89%   +0.08%     
  Complexity      323      323              
============================================
  Files          1081     1081              
  Lines         43840    43840              
  Branches       6536     6536              
============================================
+ Hits          25784    25820      +36     
+ Misses        15192    15154      -38     
- Partials       2864     2866       +2     

Impacted Files	Coverage Δ
...apache/dubbo/registry/retry/AbstractRetryTask.java	58.33% <0.00%> (-13.89%)	⬇️
...ng/transport/dispatcher/all/AllChannelHandler.java	89.65% <0.00%> (-6.90%)	⬇️
...etadata/report/support/AbstractMetadataReport.java	58.70% <0.00%> (-1.00%)	⬇️
.../dubbo/remoting/transport/netty4/NettyChannel.java	65.34% <0.00%> (-1.00%)	⬇️
...ting/zookeeper/curator/CuratorZookeeperClient.java	66.07% <0.00%> (-0.90%)	⬇️
...he/dubbo/registry/zookeeper/ZookeeperRegistry.java	57.86% <0.00%> (-0.63%)	⬇️
...figcenter/file/FileSystemDynamicConfiguration.java	59.52% <0.00%> (+0.47%)	⬆️
...he/dubbo/registry/multicast/MulticastRegistry.java	68.34% <0.00%> (+0.91%)	⬆️
...rg/apache/dubbo/common/timer/HashedWheelTimer.java	63.79% <0.00%> (+1.03%)	⬆️
.../src/main/java/org/apache/dubbo/rpc/RpcStatus.java	75.00% <0.00%> (+1.19%)	⬆️
... and 6 more

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