fix: set cache-dependency-path for requirements-docs.txt in Pages workflow

Author: RedjiJB

.github/workflows/docs.yml

@@ -32,6 +32,7 @@ jobs:
         with:
           python-version: '3.12'
           cache: pip
+          cache-dependency-path: requirements-docs.txt
 
       - name: Install MkDocs and plugins
         run: pip install -r requirements-docs.txt