ci(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] <[email protected]>

Author: dependabot[bot]

.github/workflows/build.yml

@@ -18,7 +18,7 @@ jobs:
 
     steps:
     - name: 📥 Checkout
-      uses: actions/checkout@v4
+      uses: actions/checkout@v6
 
     - name: ⚙️ Setup .NET
       uses: actions/setup-dotnet@v4

.github/workflows/codeql.yml

@@ -27,7 +27,7 @@ jobs:
 
     steps:
     - name: 📥 Checkout repository
-      uses: actions/checkout@v4
+      uses: actions/checkout@v6
 
     - name: 🔧 Setup .NET
       if: matrix.language == 'csharp'

.github/workflows/deploy-pages.yml

@@ -29,7 +29,7 @@ jobs:
 
     steps:
     - name: 📥 Checkout
-      uses: actions/checkout@v4
+      uses: actions/checkout@v6
 
     - name: ⚙️ Setup .NET
       uses: actions/setup-dotnet@v4

.github/workflows/nuget-publish.yml

@@ -22,7 +22,7 @@ jobs:
 
     steps:
     - name: 📥 Checkout
-      uses: actions/checkout@v4
+      uses: actions/checkout@v6
       with:
         fetch-depth: 0