refactor(ci): update GitHub Actions checkout action version

Author: Akinator31

.github/workflows/ci.yml

@@ -17,7 +17,7 @@ jobs:
         toolchain: [stable]
 
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
         with:
           clean: 'false'
 

.github/workflows/docs.yml

@@ -15,7 +15,7 @@ jobs:
 
     steps:
       - name: Checkout code
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
 
       - name: Setup mdBook
         uses: peaceiris/actions-mdbook@v2

.github/workflows/release-ci.yml

@@ -19,7 +19,7 @@ jobs:
     env:
       SQLX_OFFLINE: true
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
 
       - name: Set up Rust
         run: rustup update stable && rustup default stable
@@ -54,7 +54,7 @@ jobs:
     env:
       SQLX_OFFLINE: true
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
 
       - name: Set up Rust
         run: rustup update stable && rustup default stable
@@ -76,7 +76,7 @@ jobs:
     needs: build-and-test
     runs-on: ubuntu-22.04
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
 
       - name: Create release
         env:
@@ -126,7 +126,7 @@ jobs:
     env:
       SQLX_OFFLINE: true
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
 
       - name: Install Rust
         run: rustup update stable && rustup default stable
@@ -162,7 +162,7 @@ jobs:
       IMAGE_NAME: ${{ github.repository }}
     steps:
       - name: Checkout repository
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
 
       - name: Set up QEMU
         uses: docker/setup-qemu-action@v3