Judge the message whether null for metadata processor.

[KomachiSion]

Please do not create a Pull Request without creating an issue first.

What is the purpose of the change

Enhance the metadata operation stability. Handling the problem of when metadata operation throw an exception without message, the exception will be replaced by NPE and the statu machine will stop.

Brief changelog

Verifying this change

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[codecov-commenter]

Codecov Report

Merging #9951 (9a13fbf) into develop (e736455) will increase coverage by 0.20%.
The diff coverage is 20.00%.

Additional details and impacted files

@@              Coverage Diff              @@
##             develop    #9951      +/-   ##
=============================================
+ Coverage      50.35%   50.56%   +0.20%     
- Complexity      4788     4830      +42     
=============================================
  Files            861      861              
  Lines          27441    27445       +4     
  Branches        3028     3031       +3     
=============================================
+ Hits           13818    13877      +59     
+ Misses         12410    12351      -59     
- Partials        1213     1217       +4     

Impacted Files	Coverage Δ
...ng/core/v2/metadata/InstanceMetadataProcessor.java	0.00% <0.00%> (ø)
...ing/core/v2/metadata/ServiceMetadataProcessor.java	69.35% <0.00%> (-1.14%)	⬇️
...naming/core/v2/metadata/NamingMetadataManager.java	78.75% <50.00%> (-1.00%)	⬇️
...alibaba/nacos/client/config/impl/ClientWorker.java	55.59% <0.00%> (-0.20%)	⬇️
.../core/v2/event/publisher/NamingEventPublisher.java	75.94% <0.00%> (+1.26%)	⬆️
...os/client/auth/ram/identify/CredentialService.java	76.08% <0.00%> (+4.34%)	⬆️
.../nacos/api/config/ability/ServerConfigAbility.java	54.54% <0.00%> (+54.54%)	⬆️
...com/alibaba/nacos/api/ability/ServerAbilities.java	90.47% <0.00%> (+90.47%)	⬆️
...com/alibaba/nacos/api/ability/ClientAbilities.java	100.00% <0.00%> (+100.00%)	⬆️
.../nacos/api/config/ability/ClientConfigAbility.java	100.00% <0.00%> (+100.00%)	⬆️
... and 2 more

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