docs: Prepare for new sub tree

See #11925

docs/.github/workflows/spellcheck.yml

@@ -1,22 +0,0 @@
-name: "Check spelling"
-on:
-  push:
-  pull_request:
-    branches-ignore:
-      - "dependabot/**"
-
-permissions:
-  contents: read
-
-jobs:
-  spellcheck:
-    runs-on: ubuntu-latest
-    steps:
-      - uses: actions/checkout@v4
-      - uses: streetsidesoftware/cspell-action@v5
-        with:
-          check_dot_files: false
-          files: content/**/*.md
-          incremental_files_only: true
-          inline: warning
-          strict: false