Bump actions/checkout from 5 to 6 (#298)

Author: dependabot[bot]

.github/workflows/Documentation.yml

@@ -26,7 +26,7 @@ jobs:
         arch:
           - x64
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - uses: julia-actions/setup-julia@latest
         with:
           version: ${{ matrix.version }}

.github/workflows/DocumentationCleanup.yml

@@ -16,7 +16,7 @@ jobs:
       contents: write
     steps:
       - name: Checkout gh-pages branch
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
         with:
           ref: gh-pages
       - name: Delete preview and history + push changes