Only count 5xx as error in Envoy ALS receiver

[kezhenxu94]

• If this pull request closes/resolves/fixes an existing issue, replace the issue number. Closes #.
• Update the CHANGES log.

[wu-sheng]

FYI to other readers, 4xx include 404 and 403, which typically are caused by the client-side issue.

[codecov]

Codecov Report

Merging #7111 (61cbf12) into master (eace27e) will decrease coverage by 30.51%.
The diff coverage is 1.04%.

❗ Current head 61cbf12 differs from pull request most recent head 5289dec. Consider uploading reports for the commit 5289dec to get more accurate results

@@              Coverage Diff              @@
##             master    #7111       +/-   ##
=============================================
- Coverage     58.84%   28.33%   -30.52%     
=============================================
  Files          1016     1761      +745     
  Lines         25951    37288    +11337     
  Branches       2555     4936     +2381     
=============================================
- Hits          15272    10567     -4705     
- Misses         9336    25727    +16391     
+ Partials       1343      994      -349     

Impacted Files	Coverage Δ
...ver/analyzer/provider/jvm/JVMSourceDispatcher.java	0.00% <0.00%> (-97.92%)	⬇️
...zer/agent/kafka/provider/KafkaFetcherProvider.java	29.16% <0.00%> (-57.79%)	⬇️
...er/receiver/envoy/als/LogEntry2MetricsAdapter.java	49.09% <0.00%> (+49.09%)	⬆️
...erver/receiver/jvm/provider/JVMModuleProvider.java	0.00% <0.00%> (-100.00%)	⬇️
...rovider/handler/JVMMetricReportServiceHandler.java	0.00% <0.00%> (-80.00%)	⬇️
...gent/kafka/provider/handler/JVMMetricsHandler.java	74.28% <100.00%> (ø)
...he/skywalking/oal/rt/output/DispatcherContext.java	0.00% <0.00%> (-100.00%)	⬇️
...skywalking/oal/rt/output/AllDispatcherContext.java	0.00% <0.00%> (-100.00%)	⬇️
...ache/skywalking/oap/server/core/source/Source.java	0.00% <0.00%> (-100.00%)	⬇️
...che/skywalking/oap/server/core/source/Service.java	0.00% <0.00%> (-100.00%)	⬇️
... and 1781 more

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