chore: pin GitHub Action digests to semver in Renovate config (#242)

Author: tobiasdiez

renovate.json5

@@ -10,6 +10,8 @@
     ':widenPeerDependencies',
     // Disable dashboard: https://docs.renovatebot.com/key-concepts/dashboard/
     ':disableDependencyDashboard',
+    // Pin Github Actions versions: https://docs.renovatebot.com/presets-helpers/#helperspingithubactiondigeststosemver
+    'helpers:pinGitHubActionDigestsToSemver',
   ],
   schedule: [
     // Monthly, but give a 3-day window (due to throttling not all PRs may be created on the same day): https://docs.renovatebot.com/configuration-options/#schedule