ci: update checkout version

Author: infinitis

.github/workflows/ci.yml

@@ -35,7 +35,7 @@ jobs:
           - 3306:3306
         options: --health-cmd="mysqladmin ping" --health-interval=10s --health-timeout=5s --health-retries=3
     steps:
-    - uses: actions/checkout@v2
+    - uses: actions/checkout@v5
     - name: Set up Elixir
       id: beam
       uses: erlef/setup-beam@v1