Fix apdex threshold config bug when dynamic configuration is enabled.

[Ax1an]

Please answer these questions before submitting pull request

• Why submit this pull request?

• Bug fix

• New feature provided

• Improve performance

• Related issues

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Bug fix

• Bug description.

  Fix apdex threshold config bug when dynamic configuration is enabled.
  This bug will result in a large number of warn logs, even if the service-apdex-threshold.yml file exist.
  

• How to fix?

  Optimize processing logic.
  If there is a core.default.apdexThreshold in the dynamic configuration, use it.
  If there is no core.default.apdexThreshold in the dynamic configuration, the service-apdex-threshold.yml file is read. And it is read only once when the configuration is switched. For example, delete core.default.apdexThreshold in the dynamic configuration.
  Only print the warn log if the service-apdex-threshold.yml file does not exist.

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New feature or improvement

• Describe the details and related test reports.

[codecov]

Codecov Report

Merging #5097 into master will decrease coverage by 0.42%.
The diff coverage is 12.50%.

@@             Coverage Diff              @@
##             master    #5097      +/-   ##
============================================
- Coverage     53.09%   52.66%   -0.43%     
+ Complexity     2985     2911      -74     
============================================
  Files          1417     1417              
  Lines         30719    30724       +5     
  Branches       3417     3422       +5     
============================================
- Hits          16310    16182     -128     
- Misses        13605    13738     +133     
  Partials        804      804              

Impacted Files	Coverage Δ	Complexity Δ
...oap/server/core/analysis/ApdexThresholdConfig.java	54.05% <12.50%> (-11.58%)	4.00 <0.00> (ø)
...ing/oap/server/library/util/ProtoBufJsonUtils.java	0.00% <0.00%> (-90.00%)	0.00% <0.00%> (-2.00%)
...tworkalias/NetworkAddressAliasSetupDispatcher.java	11.11% <0.00%> (-88.89%)	1.00% <0.00%> (-1.00%)
...ler/v8/rest/ManagementServiceKeepAliveHandler.java	32.00% <0.00%> (-64.00%)	2.00% <0.00%> (-1.00%)
...rest/ManagementServiceReportPropertiesHandler.java	27.58% <0.00%> (-62.07%)	2.00% <0.00%> (-2.00%)
...lysis/manual/networkalias/NetworkAddressAlias.java	2.43% <0.00%> (-56.10%)	0.00% <0.00%> (-5.00%)
...p/server/core/source/NetworkAddressAliasSetup.java	33.33% <0.00%> (-50.01%)	2.00% <0.00%> (-1.00%)
...erver/library/client/jdbc/JDBCClientException.java	0.00% <0.00%> (-50.00%)	0.00% <0.00%> (-1.00%)
...r/listener/NetworkAddressAliasMappingListener.java	36.36% <0.00%> (-39.40%)	4.00% <0.00%> (-1.00%)
.../v8/rest/TraceSegmentReportBaseServletHandler.java	42.30% <0.00%> (-30.77%)	2.00% <0.00%> (-2.00%)
... and 17 more

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[wu-sheng]

Are you trying to fail back to config file? I am not sure whether this is a recommended way. I think other config doesn't follow this. Such as alarm. Could you recheck?

[wu-sheng]

Behavior should be consistent acrosee all config items. I think you should fix the dynamic configuration center logic, rather than fixing like this.