Update aquasec/trivy Docker tag to v0.21.3

This MR contains the following updates:

Package	Type	Update	Change
aquasec/trivy	ironbank-docker	patch	0.21.2 -> 0.21.3
aquasec/trivy		patch	0.21.2 -> 0.21.3
aquasec/trivy	stage	patch	0.21.2 -> 0.21.3

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