chore(deps): update actions/checkout action to v4

Author: renovate[bot]

.github/workflows/buildtest.yml

@@ -10,7 +10,7 @@ jobs:
   build:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v3.0.2
+    - uses: actions/checkout@v4.0.0
     - uses: actions/setup-node@v3.4.1
       with:
          node-version: '18.x'

.github/workflows/codeql-analysis.yml

@@ -38,7 +38,7 @@ jobs:
 
     steps:
     - name: Checkout repository
-      uses: actions/checkout@v3
+      uses: actions/checkout@v4
 
     # Initializes the CodeQL tools for scanning.
     - name: Initialize CodeQL