[8.0](backport #29470) Enhance filter check in k8s event metricset

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This is an automatic backport of pull request #29470 done by Mergify.

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• Start Time: 2021-12-16T20:07:46.558+0000

• Duration: 136 min 39 sec

• Commit: 2cf11b0

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Test	Results
Failed	0
Passed	47793
Skipped	4148
Total	51941

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