fix: update BUILD_PATH to current directory and enable sparse checkout for docs

Author: pascalinthecloud

.github/workflows/docs_astro_deploy.yaml

@@ -25,7 +25,7 @@ concurrency:
   cancel-in-progress: false
 
 env:
-  BUILD_PATH: "docs" # default value when not using subfolders
+  BUILD_PATH: "." # default value when not using subfolders
   # BUILD_PATH: subfolder
 
 jobs:
@@ -35,6 +35,8 @@ jobs:
     steps:
       - name: Checkout
         uses: actions/checkout@v4
+        with:
+          sparse-checkout: docs
       - name: Detect package manager
         id: detect-package-manager
         run: |