chore(deps): update actions/checkout action to v5

Author: renovate[bot]

.github/workflows/editorconfig-checks.yaml

@@ -8,7 +8,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout repository
-        uses: actions/checkout@v4
+        uses: actions/checkout@v5
 
       - name: Check files for EditorConfig compliance
         uses: editorconfig-checker/action-editorconfig-checker@v2

.github/workflows/nix-flake-check.yaml

@@ -9,7 +9,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout repository
-        uses: actions/checkout@v4
+        uses: actions/checkout@v5
 
       - name: Install Nix
         uses: cachix/install-nix-action@v31

.github/workflows/nix-fmt-checks.yaml

@@ -9,7 +9,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout repository
-        uses: actions/checkout@v4
+        uses: actions/checkout@v5
 
       - name: Install Nix
         uses: cachix/install-nix-action@v31