Bump actions/checkout from 3 to 4

Bumps [actions/checkout](https://github.com/actions/checkout) from 3 to 4.
- [Release notes](https://github.com/actions/checkout/releases)
- [Changelog](https://github.com/actions/checkout/blob/main/CHANGELOG.md)
- [Commits](actions/checkout@v3...v4)

---
updated-dependencies:
- dependency-name: actions/checkout
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <support@github.com>

.github/workflows/codeql.yml

@@ -24,7 +24,7 @@ jobs:
 
     steps:
       - name: Checkout
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4
 
       - name: Initialize CodeQL
         uses: github/codeql-action/init@v2

.github/workflows/linters.yaml

@@ -23,7 +23,7 @@ jobs:
             engine: docker
 
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
         with:
           fetch-depth: 0
 
@@ -41,7 +41,7 @@ jobs:
 
     steps:
       - name: Check out repo
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4
 
       - name: Run flake8 for Python 3
         uses: containerbuildsystem/actions/flake8@master
@@ -52,7 +52,7 @@ jobs:
 
     steps:
       - name: Check out repo
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4
 
       - name: Run markdownlint
         uses: DavidAnson/markdownlint-cli2-action@v16
@@ -70,7 +70,7 @@ jobs:
             engine: docker
 
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
 
       - run: ./test.sh
         env:
@@ -86,7 +86,7 @@ jobs:
 
     steps:
       - name: Check out repo
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4
 
       - name: Run ShellCheck
         uses: containerbuildsystem/actions/shellcheck@master

.github/workflows/unittests.yaml

@@ -29,7 +29,7 @@ jobs:
 
     steps:
       - name: Check out repo
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4
 
       - name: pytests via test.sh
         env: