Ci: Update checkout action

Author: TheOneRing

.github/workflows/clang-format.yml

@@ -7,7 +7,7 @@ jobs:
     runs-on: ubuntu-latest
 
     steps:
-    - uses: actions/checkout@v2
+    - uses: actions/checkout@v4
       with:
         fetch-depth: 2
     - uses: owncloud-ci/git-clang-format-lint@master

.github/workflows/main.yml

@@ -63,7 +63,7 @@ jobs:
 
     steps:
     - name: Check out source code
-      uses: actions/checkout@v2
+      uses: actions/checkout@v4
       with:
         fetch-depth: ${{ matrix.fetch-depth }}
         submodules: true

.github/workflows/translate.yml

@@ -22,7 +22,7 @@ jobs:
       TX_TOKEN: ${{ secrets.TX_TOKEN }}
 
     steps:
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v4
         with:
           submodules: recursive
           ref: "4"