Bump aquasecurity/trivy-action from 0.20.0 to 0.21.0

Bumps [aquasecurity/trivy-action](https://github.com/aquasecurity/trivy-action) from 0.20.0 to 0.21.0.
- [Release notes](https://github.com/aquasecurity/trivy-action/releases)
- [Commits](aquasecurity/trivy-action@0.20.0...0.21.0)

---
updated-dependencies:
- dependency-name: aquasecurity/trivy-action
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

.github/workflows/trivy.yml

@@ -31,7 +31,7 @@ jobs:
           docker build -t "ams21/tor-relay:latest" .
 
       - name: Run Trivy vulnerability scanner
-        uses: aquasecurity/trivy-action@0.20.0
+        uses: aquasecurity/trivy-action@0.21.0
         with:
           image-ref: 'ams21/tor-relay:latest'
           format: 'template'