ci: bump actions/checkout from 4 to 6 (#2738)

Bumps [actions/checkout](https://github.com/actions/checkout) from 4 to 6.
- [Release notes](https://github.com/actions/checkout/releases)
- [Changelog](https://github.com/actions/checkout/blob/main/CHANGELOG.md)
- [Commits](actions/checkout@v4...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] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

.github/workflows/format.yml

@@ -8,7 +8,7 @@ jobs:
     if: ${{ false }} 
     steps:
       - name: Checkout
-        uses: actions/checkout@v6.0.2
+        uses: actions/checkout@v6
         with:
           fetch-depth: 0   
       - name: Prettify code

.github/workflows/j3o-scan.yml

@@ -28,7 +28,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout repository
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
 
       - name: Set up Java
         uses: actions/setup-java@v4

.github/workflows/main.yml

@@ -64,7 +64,7 @@ jobs:
     permissions:
       contents: read
     steps:
-      - uses: actions/checkout@v6.0.2
+      - uses: actions/checkout@v6
       - name: Setup the java environment
         uses: actions/setup-java@v5.2.0
         with:
@@ -91,7 +91,7 @@ jobs:
     permissions:
       contents: read
     steps:
-      - uses: actions/checkout@v6.0.2
+      - uses: actions/checkout@v6
       - name: Setup the java environment
         uses: actions/setup-java@v5.2.0
         with:
@@ -119,7 +119,7 @@ jobs:
     permissions:
       contents: read
     steps:
-      - uses: actions/checkout@v6.0.2
+      - uses: actions/checkout@v6
       - name: Start xvfb
         run: |
           Xvfb :99 -ac -screen 0 1024x768x16 &
@@ -171,7 +171,7 @@ jobs:
           xcode-version: '15.1.0'
 
       - name: Clone the repo
-        uses: actions/checkout@v6.0.2
+        uses: actions/checkout@v6
         with:
           fetch-depth: 1
 
@@ -198,7 +198,7 @@ jobs:
 
     steps:
       - name: Clone the repo
-        uses: actions/checkout@v6.0.2
+        uses: actions/checkout@v6
         with:
           fetch-depth: 1
 
@@ -255,7 +255,7 @@ jobs:
 
     steps:
       - name: Clone the repo
-        uses: actions/checkout@v6.0.2
+        uses: actions/checkout@v6
         with:
           fetch-depth: 1
 
@@ -447,7 +447,7 @@ jobs:
 
       # We need to clone everything again for uploadToMaven.sh ...
       - name: Clone the repo
-        uses: actions/checkout@v6.0.2
+        uses: actions/checkout@v6
         with:
           fetch-depth: 1
 
@@ -497,7 +497,7 @@ jobs:
 
       # We need to clone everything again for uploadToCentral.sh ...
       - name: Clone the repo
-        uses: actions/checkout@v6.0.2
+        uses: actions/checkout@v6
         with:
           fetch-depth: 1