failover triggered mistakenly

[nkorange]

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What is the purpose of the change

Fix failover switch triggered mistakenly and optimise metrics

Brief changelog

1. only mute notification for the services in failover service list.
2. optimise the using of micrometer.

Verifying this change

1. turn on failover and put svc.1 to the failover list.
2. subscribe svc.1 and svc.2.
3. trigger instance list change to svc.1 and svc.2.
4. observe that svc.1 has no notification, while svc.2 has.

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[codecov-commenter]

Codecov Report

Attention: Patch coverage is 7.14286% with 13 lines in your changes are missing coverage. Please review.

Project coverage is 67.76%. Comparing base (b7c3905) to head (ebbb5fc).

Additional details and impacted files

@@              Coverage Diff              @@
##             develop   #11536      +/-   ##
=============================================
- Coverage      67.80%   67.76%   -0.05%     
+ Complexity      8892     8891       -1     
=============================================
  Files           1237     1237              
  Lines          40443    40446       +3     
  Branches        4286     4288       +2     
=============================================
- Hits           27424    27409      -15     
- Misses         11046    11063      +17     
- Partials        1973     1974       +1     

Files	Coverage Δ
...a/nacos/client/naming/cache/ServiceInfoHolder.java	92.03% <0.00%> (ø)
...a/nacos/client/naming/backups/FailoverReactor.java	73.40% <7.69%> (-17.81%)	⬇️

... and 1 file with indirect coverage changes

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