Fix workflow file:

Author: duncte123

.github/workflows/build.yml

@@ -25,12 +25,12 @@ jobs:
         uses: actions/setup-node@v2
         with:
           node-version: ${{ matrix.node-version }}
-        - uses: actions/cache@v2
-          with:
-            path: ~/.npm
-            key: ${{ runner.os }}-node-${{ hashFiles('**/package-lock.json') }}
-            restore-keys: |
-              ${{ runner.os }}-node-
+      - uses: actions/cache@v2
+        with:
+          path: ~/.npm
+          key: ${{ runner.os }}-node-${{ hashFiles('**/package-lock.json') }}
+          restore-keys: |
+            ${{ runner.os }}-node-
       # we may need this, not sure
       # - run: npm install json -g
       - run: npm ci