Update actions/checkout action to v4

Signed-off-by: Renovate Bot <bot@renovateapp.com>

Author: renovate[bot]

.github/workflows/check-python-syntax.yml

@@ -17,7 +17,7 @@ jobs:
   check-python-syntax:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - uses: actions/setup-python@v4
         with:
           python-version: '3.x'

.github/workflows/check-yaml-syntax.yml

@@ -19,7 +19,7 @@ jobs:
   check-yaml-syntax:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - uses: actions/setup-python@v4
         with:
           python-version: '3.x'

.github/workflows/test-python-setup.yml

@@ -17,7 +17,7 @@ jobs:
   test-python-setup:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - uses: actions/setup-python@v4
         with:
           python-version: '3.x'