Bump aquasecurity/trivy-action from 0.20.0 to 0.21.0 #171

Job	Run time
Check whether tests need to be run based on diff	16s
Verify docs and spelling	29s
Unit test (ubuntu-latest)	6m 38s
Build Antrea and antctl binaries	9m 51s
Golangci-lint (macos-latest)	3m 15s
Golangci-lint (ubuntu-latest)	7m 55s
Integration test	10m 20s
Unit test (windows-2022)	11m 24s
Go benchmark test	4m 46s
Check tidy, code generation and manifest	5m 21s
Build Antrea Windows binaries	1m 55s
	1h 2m 10s

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