Bump actions/checkout from 2.3.4 to 2.4.0

Bumps [actions/checkout](https://github.com/actions/checkout) from 2.3.4 to 2.4.0.
- [Release notes](https://github.com/actions/checkout/releases)
- [Changelog](https://github.com/actions/checkout/blob/main/CHANGELOG.md)
- [Commits](https://github.com/actions/checkout/compare/v2.3.4...v2.4.0)

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

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

.github/workflows/cli_setup.yml

@@ -17,7 +17,7 @@ jobs:
         python-version: [3.7, 3.8, 3.9]
 
     steps:
-    - uses: actions/checkout@v2.3.4
+    - uses: actions/checkout@v2.4.0
 
     - name: Set up Python ${{ matrix.python-version }}
       uses: actions/setup-python@v2.2.2
@@ -33,7 +33,7 @@ jobs:
       QMK_HOME: $HOME/qmk_firmware
 
     steps:
-    - uses: actions/checkout@v2.3.4
+    - uses: actions/checkout@v2.4.0
 
     - name: (MSYS2) Setup and install dependencies
       uses: msys2/setup-msys2@v2

.github/workflows/codeql-analysis.yml

@@ -39,7 +39,7 @@ jobs:
 
     steps:
     - name: Checkout repository
-      uses: actions/checkout@v2.3.4
+      uses: actions/checkout@v2.4.0
 
     # Initializes the CodeQL tools for scanning.
     - name: Initialize CodeQL

.github/workflows/python-publish.yml

@@ -17,7 +17,7 @@ jobs:
     runs-on: ubuntu-latest
 
     steps:
-    - uses: actions/checkout@v2.3.4
+    - uses: actions/checkout@v2.4.0
     - name: Set up Python
       uses: actions/setup-python@v2.2.2
       with: