chore(deps): pin actions/checkout action to v6.0.3

Author: renovate[bot]

.github/workflows/checks.yaml

@@ -13,7 +13,7 @@ jobs:
     if: github.event_name == 'push' || !startsWith(github.head_ref, 'renovate/')
     steps:
       - name: Checkout code
-        uses: actions/checkout@v6
+        uses: actions/checkout@df4cb1c069e1874edd31b4311f1884172cec0e10 # v6.0.3
 
       - name: Setup Node.js
         uses: actions/setup-node@v6
@@ -33,7 +33,7 @@ jobs:
     if: github.event_name == 'push' || !startsWith(github.head_ref, 'renovate/')
     steps:
       - name: Checkout code
-        uses: actions/checkout@v6
+        uses: actions/checkout@df4cb1c069e1874edd31b4311f1884172cec0e10 # v6.0.3
 
       - name: Setup Node.js
         uses: actions/setup-node@v6

.github/workflows/docs.yaml

@@ -8,7 +8,7 @@ jobs:
   build-docs:
     runs-on: ubuntu-slim
     steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@df4cb1c069e1874edd31b4311f1884172cec0e10 # v6.0.3
       - name: Setup Node.js
         uses: actions/setup-node@v6
         with:

.github/workflows/release.yaml

@@ -42,7 +42,7 @@ jobs:
     timeout-minutes: 15
     steps:
       - name: Checkout code
-        uses: actions/checkout@v6
+        uses: actions/checkout@df4cb1c069e1874edd31b4311f1884172cec0e10 # v6.0.3
 
       - name: Setup Node.js
         uses: actions/setup-node@v6