chore(actions): bump step-security/harden-runner from 2.20.1 to 2.21.0 (#101)

Bumps [step-security/harden-runner](https://github.com/step-security/harden-runner) from 2.20.1 to 2.21.0.
- [Release notes](https://github.com/step-security/harden-runner/releases)
- [Commits](step-security/harden-runner@b09bb98...05e3151)

---
updated-dependencies:
- dependency-name: step-security/harden-runner
  dependency-version: 2.21.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
Co-authored-by: Leonardo <14614620+aardbol@users.noreply.github.com>

Author: dependabot[bot]

.github/workflows/dependency-review.yml

@@ -19,7 +19,7 @@ jobs:
     runs-on: ubuntu-24.04
     steps:
       - name: Harden the runner (Audit all outbound calls)
-        uses: step-security/harden-runner@b09bb98e06d4d774595224525879c09bc6e98c40 # v2.20.1
+        uses: step-security/harden-runner@05e31511f85b41b11d1cf0ef85d0992719546e2c # v2.21.0
         with:
           egress-policy: audit