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/ci.yml

@@ -12,7 +12,7 @@ jobs:
   test:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
 
       - name: Install uv
         uses: astral-sh/setup-uv@v5

.github/workflows/codeql.yml

@@ -20,7 +20,7 @@ jobs:
   analyze:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
 
       - name: Initialize CodeQL
         uses: github/codeql-action/init@v3

.github/workflows/pages.yml

@@ -24,7 +24,7 @@ jobs:
   build:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
 
       - name: Install uv
         uses: astral-sh/setup-uv@v5

.github/workflows/release-check.yml

@@ -15,7 +15,7 @@ jobs:
   artifacts:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
 
       - name: Install uv
         uses: astral-sh/setup-uv@v5

.github/workflows/secret-patterns.yml

@@ -12,7 +12,7 @@ jobs:
   scan:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
 
       - name: Run open-source content audit
         run: python3 scripts/open_source_audit.py --target public-repo