Merge pull request #291 from ISISComputingGroup/dependabot/github_actions/actions/checkout-6

Bump actions/checkout from 4 to 6

Author: Tom-Willemsen

.github/workflows/documentation.yml

@@ -6,7 +6,7 @@ jobs:
   spellcheck:
     runs-on: "windows-latest"
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
         with:
           fetch-depth: 0
       - uses: actions/setup-python@v5