Fix syntax err in workflow "ci"

Signed-off-by: Jiahao XU <Jiahao_XU@outlook.com>

.github/workflows/ci.yml

@@ -11,22 +11,21 @@ jobs:
   test:
     name: test
     runs-on: ubuntu-latest
-
-  steps:
-    - uses: actions/checkout@v2
-    - name: Configure toolchain
-      uses: actions-rs/toolchain@v1
-      with:
-        toolchain: stable
-        override: true
-    - name: Configure caching
-      uses: actions/cache@v2
-      with:
-        key: ${{ matrix.os }}-${{ matrix.target }}-testing
-        path: |
-          ${{ env.HOME }}/.cargo
-          target
-    - name: test
-      uses: actions-rs/cargo@v1
-      with:
-        command: test
+    steps:
+      - uses: actions/checkout@v2
+      - name: Configure toolchain
+        uses: actions-rs/toolchain@v1
+        with:
+          toolchain: stable
+          override: true
+      - name: Configure caching
+        uses: actions/cache@v2
+        with:
+          key: ${{ matrix.os }}-${{ matrix.target }}-testing
+          path: |
+            ${{ env.HOME }}/.cargo
+            target
+      - name: test
+        uses: actions-rs/cargo@v1
+        with:
+          command: test