added filter option & tests

.github/workflows/test.yml

@@ -72,6 +72,17 @@ jobs:
         shell: bash
         run: __test__/verify-side-by-side.sh
 
+      # Filter
+      - name: Fetch filter
+        uses: ./
+        with:
+          filter: 'blob:none'
+          path: fetch-filter
+
+      - name: Verify fetch filter
+        run: __test__/verify-fetch-filter.sh
+    
+
       # Sparse checkout
       - name: Sparse checkout
         uses: ./