Update actions/checkout action to v7 (#27)

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

Author: renovate[bot]

.github/workflows/pipeline.yml

@@ -19,7 +19,7 @@ jobs:
     container: hashicorp/terraform
     steps:
       - name: Checkout repository
-        uses: actions/checkout@v6
+        uses: actions/checkout@v7
       - name: Terraform Format Check
         run: terraform fmt -check -recursive -diff
 
@@ -29,7 +29,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout repository
-        uses: actions/checkout@v6
+        uses: actions/checkout@v7
       - name: Set validation matrix
         id: set-matrix
         run: |
@@ -54,7 +54,7 @@ jobs:
           - 4566:4566
     steps:
       - name: Checkout repository
-        uses: actions/checkout@v6
+        uses: actions/checkout@v7
       - name: Terraform Init
         run: terraform init -upgrade
         working-directory: ${{ matrix.dir }}