Bump step-security/harden-runner from 2.12.2 to 2.13.0 (#144)

Bumps [step-security/harden-runner](https://github.com/step-security/harden-runner) from 2.12.2 to 2.13.0.
- [Release notes](https://github.com/step-security/harden-runner/releases)
- [Commits](step-security/harden-runner@6c439dc...ec9f2d5)

---
updated-dependencies:
- dependency-name: step-security/harden-runner
  dependency-version: 2.13.0
  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>

Author: dependabot[bot]

.github/workflows/mix-dependency-submission.yml

@@ -19,7 +19,7 @@ jobs:
 
     steps:
       - name: Harden Runner
-        uses: step-security/harden-runner@6c439dc8bdf85cadbbce9ed30d1c7b959517bc49 # v2.12.2
+        uses: step-security/harden-runner@ec9f2d5744a09debf3a187a3f4f675c53b671911 # v2.13.0
         with:
           egress-policy: audit