[SECENG-364] Pin GitHub Actions to commit SHAs (#86)

Author: sginovker

.github/dependabot.yml

@@ -0,0 +1,13 @@
+version: 2
+updates:
+- package-ecosystem: "github-actions"
+  directory: "/"
+  commit-message:
+    prefix: "[bot] "
+  cooldown:
+    default-days: 7
+  schedule:
+    interval: "weekly"
+    day: "wednesday"
+    time: "11:00"
+    timezone: "America/Los_Angeles"

.github/workflows/linter-rubocop.yml

@@ -11,7 +11,7 @@ jobs:
         uses: actions/checkout@main
 
       - name: Set up Ruby
-        uses: ruby/setup-ruby@v1
+        uses: ruby/setup-ruby@e65c17d16e57e481586a6a5a0282698790062f92 # v1
         with:
           bundler-cache: true