Fix metadata proxy load filter

[AlbumenJ]

What is the purpose of the change

Fix #11716

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.
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• 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.
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[chickenlj]

LGTM.

[sonarqubecloud]

Kudos, SonarCloud Quality Gate passed!   

0 Bugs
0 Vulnerabilities
0 Security Hotspots
0 Code Smells

0.0% Coverage
0.0% Duplication

[codecov-commenter]

Codecov Report

Merging #11769 (3bfb17d) into 3.1 (7277c15) will increase coverage by 0.00%.
The diff coverage is 100.00%.

@@            Coverage Diff            @@
##                3.1   #11769   +/-   ##
=========================================
  Coverage     64.68%   64.69%           
  Complexity       14       14           
=========================================
  Files          1431     1431           
  Lines         60034    60034           
  Branches       8827     8827           
=========================================
+ Hits          38832    38838    +6     
+ Misses        17119    17115    -4     
+ Partials       4083     4081    -2     

Impacted Files	Coverage Δ
.../dubbo/registry/client/metadata/MetadataUtils.java	65.74% <100.00%> (ø)
...e/dubbo/rpc/protocol/tri/transport/WriteQueue.java	64.28% <0.00%> (-9.53%)	⬇️
...ache/dubbo/common/extension/ExtensionDirector.java	93.33% <0.00%> (-3.34%)	⬇️
...egistry/kubernetes/KubernetesServiceDiscovery.java	77.83% <0.00%> (-2.36%)	⬇️
.../src/main/java/org/apache/dubbo/rpc/RpcStatus.java	80.95% <0.00%> (-1.20%)	⬇️
.../dubbo/remoting/transport/netty4/NettyChannel.java	72.64% <0.00%> (-0.95%)	⬇️
...he/dubbo/registry/zookeeper/ZookeeperRegistry.java	61.57% <0.00%> (+0.52%)	⬆️
...ng/zookeeper/curator5/Curator5ZookeeperClient.java	77.04% <0.00%> (+0.81%)	⬆️
...adata/store/zookeeper/ZookeeperMetadataReport.java	72.34% <0.00%> (+1.06%)	⬆️
...c/main/java/org/apache/dubbo/rpc/RpcException.java	83.87% <0.00%> (+3.22%)	⬆️
... and 6 more

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[AlbumenJ]

Integration test cases: apache/dubbo-samples#786