fix gatsby cache

.github/workflows/main.yml

@@ -27,13 +27,15 @@ jobs:
           cache: yarn
       - name: Install dependencies
         run: yarn install --prod --pure-lockfile
-      - name: Cache gatsby cache
+      - name: Gatsby cache
         uses: actions/cache@v2
         with:
           key: ${{ runner.os }}-gatsby-build-${{ github.run_id }}
           restore-keys: |
             ${{ runner.os }}-gatsby-build-
-          path: .cache
+          path: |
+            public
+            .cache
       - name: Build
         run: yarn run build
       - name: upload