Bump step-security/harden-runner from 2.11.1 to 2.12.0

Bumps [step-security/harden-runner](https://github.com/step-security/harden-runner) from 2.11.1 to 2.12.0.
- [Release notes](https://github.com/step-security/harden-runner/releases)
- [Commits](step-security/harden-runner@c6295a6...0634a26)

---
updated-dependencies:
- dependency-name: step-security/harden-runner
  dependency-version: 2.12.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

Author: dependabot[bot]

.github/workflows/push_gem.yml

@@ -18,7 +18,7 @@ jobs:
     steps:
       # Set up
       - name: Harden Runner
-        uses: step-security/harden-runner@c6295a65d1254861815972266d5933fd6e532bdf # v2.11.1
+        uses: step-security/harden-runner@0634a2670c59f64b4a01f0f96f84700a4088b9f0 # v2.12.0
         with:
           egress-policy: audit