SCB-993 search sc cluster when key mismatch with aggregator cache

[little-cui]

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[codecov-io]

Codecov Report

Merging #493 into master will decrease coverage by 0.49%.
The diff coverage is 25.44%.

@@            Coverage Diff            @@
##           master     #493     +/-   ##
=========================================
- Coverage   59.74%   59.25%   -0.5%     
=========================================
  Files         165      166      +1     
  Lines       13796    13880     +84     
=========================================
- Hits         8243     8224     -19     
- Misses       4973     5072     +99     
- Partials      580      584      +4

Impacted Files	Coverage Δ
server/service/event/instance_event_handler.go	7.54% <0%> (-0.3%)	⬇️
pkg/util/util.go	62.02% <0%> (-4.2%)	⬇️
...rver/plugin/pkg/discovery/servicecenter/indexer.go	0% <0%> (-35%)	⬇️
...erver/plugin/pkg/discovery/servicecenter/cacher.go	33.33% <0%> (ø)	⬆️
server/service/util/util.go	80% <0%> (-10%)	⬇️
server/service/event/dependency_event_handler.go	15.17% <0%> (-0.14%)	⬇️
scctl/pkg/plugin/diagnose/diagnose.go	64.77% <0%> (ø)	⬆️
...rver/plugin/pkg/discovery/servicecenter/adaptor.go	0% <0%> (ø)	⬆️
server/service/event/rule_event_handler.go	8.33% <0%> (-0.37%)	⬇️
server/service/event/tag_event_handler.go	7.14% <0%> (-0.27%)	⬇️
... and 16 more

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[coveralls]

Coverage decreased (-0.4%) to 61.748% when pulling bcee692 on little-cui:bug into 0a0b1fd on apache:master.