build(deps): bump step-security/harden-runner from 2.3.1 to 2.4.0 (#248)

Bumps [step-security/harden-runner](https://github.com/step-security/harden-runner) from 2.3.1 to 2.4.0.
- [Release notes](https://github.com/step-security/harden-runner/releases)
- [Commits](step-security/harden-runner@6b3083a...128a634)

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

.github/workflows/udpate-docs.yml

@@ -30,7 +30,7 @@ jobs:
     steps:
 
     - name: Harden Runner
-      uses: step-security/harden-runner@6b3083af2869dc3314a0257a42f4af696cc79ba3
+      uses: step-security/harden-runner@128a63446a954579617e875aaab7d2978154e969
       with:
         egress-policy: audit # TODO: change to 'egress-policy: block' after couple of runs