chore(deps): bump actions/checkout from 5 to 6

Bumps [actions/checkout](https://github.com/actions/checkout) from 5 to 6.
- [Release notes](https://github.com/actions/checkout/releases)
- [Changelog](https://github.com/actions/checkout/blob/main/CHANGELOG.md)
- [Commits](actions/checkout@v5...v6)

---
updated-dependencies:
- dependency-name: actions/checkout
  dependency-version: '6'
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

.github/workflows/build-and-run-example-project.yml

@@ -17,7 +17,7 @@ jobs:
 
     steps:
       - name: Checkout Repository
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
 
       - name: Set up JDK 8
         uses: actions/setup-java@v5
@@ -63,7 +63,7 @@ jobs:
 
     steps:
       - name: Checkout Maven Plugin Repository
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
         with:
           repository: TongchengOpenSource/smart-doc-maven-plugin
           token: ${{ secrets.GITHUB_TOKEN }}
@@ -130,7 +130,7 @@ jobs:
 
     steps:
       - name: Checkout Example Project
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
         with:
           repository: smart-doc-group/smart-doc-example-cn
           token: ${{ secrets.GITHUB_TOKEN }}
@@ -259,7 +259,7 @@ jobs:
 
     steps:
       - name: Checkout Example Project
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
         with:
           repository: smart-doc-group/smart-doc-example-cn
           token: ${{ secrets.GITHUB_TOKEN }}

.github/workflows/deploy-to-maven-central.yml

@@ -11,7 +11,7 @@ jobs:
 
     steps:
       - name: Checkout Plugin Repository
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
 
       - name: Set Up JDK
         uses: actions/setup-java@v5

.github/workflows/maven.yml

@@ -20,7 +20,7 @@ jobs:
     runs-on: ubuntu-latest
 
     steps:
-    - uses: actions/checkout@v5
+    - uses: actions/checkout@v6
     - name: Set up JDK 8
       uses: actions/setup-java@v5
       with:

.github/workflows/spring-javaformat-validate.yml

@@ -8,7 +8,7 @@ jobs:
 
     steps:
       - name: Checkout repository
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
 
       - name: Set up JDK 8
         uses: actions/setup-java@v5