Update actions/checkout action to v4 (#33)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

.github/workflows/lambda.yml

@@ -40,7 +40,7 @@ jobs:
       # Checkout the repository
       ##################################################
       - name: Checkout Repository
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4
         with:
           fetch-depth: 0
 

.github/workflows/validate-codeowners.yml

@@ -9,7 +9,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
     - name: "Checkout source code at current commit"
-      uses: actions/checkout@v3
+      uses: actions/checkout@v4
     - uses: mszostok/[email protected]
       if: github.event.pull_request.head.repo.full_name == github.repository
       name: "Full check of CODEOWNERS"