chore(deps): update actions/checkout action to v6 (#101)

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

Author: renovate[bot]

.github/workflows/coding-standards.yml

@@ -13,7 +13,7 @@ jobs:
 
     steps:
       - name: "Checkout"
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
 
       - name: "Install PHP"
         uses: "shivammathur/setup-php@v2"

.github/workflows/continuous-integration.yml

@@ -26,7 +26,7 @@ jobs:
 
     steps:
       - name: "Checkout"
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
         with:
           fetch-depth: 2
 
@@ -59,7 +59,7 @@ jobs:
 
     steps:
       - name: "Checkout"
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
         with:
           fetch-depth: 2
 

.github/workflows/static-analysis.yml

@@ -13,7 +13,7 @@ jobs:
 
     steps:
       - name: "Checkout code"
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
 
       - name: "Install PHP"
         uses: "shivammathur/setup-php@v2"