chore(deps): bump actions/checkout from 4 to 6

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>

Author: dependabot[bot]

.github/workflows/check-ps3netsrv-version.yml

@@ -7,7 +7,7 @@ jobs:
   update-version:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
         with:
           token: ${{ secrets.REPO_SCOPED_TOKEN }}
           ref: main

.github/workflows/docker-publish.yml

@@ -33,7 +33,7 @@ jobs:
 
     steps:
       - name: Checkout
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
 
       - name: Set up Docker Buildx
         id: buildx_test
@@ -79,7 +79,7 @@ jobs:
 
     steps:
       - name: Checkout
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
         with:
           ref: ${{ github.ref }}
 
@@ -190,7 +190,7 @@ jobs:
 
       - name: Checkout main
         if: steps.prep.outputs.release == 'true'
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
         with:
           ref: main