meta: bump step-security/harden-runner from 2.19.4 to 2.20.0

Bumps [step-security/harden-runner](https://github.com/step-security/harden-runner) from 2.19.4 to 2.20.0.
- [Release notes](https://github.com/step-security/harden-runner/releases)
- [Commits](step-security/harden-runner@9af89fc...bf7454d)

---
updated-dependencies:
- dependency-name: step-security/harden-runner
  dependency-version: 2.20.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>
PR-URL: #64926
Reviewed-By: Aviv Keller <me@aviv.sh>
Reviewed-By: Trivikram Kamat <trivikr.dev@gmail.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>

Author: dependabot[bot]

.github/workflows/scorecard.yml

@@ -36,7 +36,7 @@ jobs:
 
     steps:
       - name: Harden Runner
-        uses: step-security/harden-runner@9af89fc71515a100421586dfdb3dc9c984fbf411  # v2.19.4
+        uses: step-security/harden-runner@bf7454d06d71f1098171f2acdf0cd4708d7b5920  # v2.20.0
         with:
           egress-policy: audit  # TODO: change to 'egress-policy: block' after couple of runs