build(deps): Bump step-security/harden-runner from 2.7.0 to 2.8.1

Bumps [step-security/harden-runner](https://github.com/step-security/harden-runner) from 2.7.0 to 2.8.1.
- [Release notes](https://github.com/step-security/harden-runner/releases)
- [Commits](step-security/harden-runner@63c24ba...17d0e2b)

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

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

.github/workflows/cibuild.yml

@@ -25,7 +25,7 @@ jobs:
       BUNDLE_PATH: vendor/bundle
     steps:
     - name: Harden Runner
-      uses: step-security/harden-runner@63c24ba6bd7ba022e95695ff85de572c04a18142 # v2.7.0
+      uses: step-security/harden-runner@17d0e2bd7d51742c71671bd19fa12bdc9d40a3d6 # v2.8.1
       with:
         egress-policy: audit # TODO: change to 'egress-policy: block' after couple of runs