Update actions/checkout version

Author: halx99

.github/workflows/ci.yml

@@ -10,23 +10,23 @@ jobs:
   windows:
     runs-on: windows-latest
     steps:
-    - uses: actions/checkout@v4
+    - uses: actions/checkout@v6
     - name: CI
       shell: pwsh
       run: |
         .\wenv install
   ubuntu:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v4
+    - uses: actions/checkout@v6
     - name: CI
       shell: pwsh
       run: |
         ./wenv install
   macos:
     runs-on: macos-latest
     steps:
-    - uses: actions/checkout@v4
+    - uses: actions/checkout@v6
     - name: CI
       shell: pwsh
       run: |