Update CI test cmd

Author: risenW

.github/workflows/node.js.yml

@@ -24,7 +24,4 @@ jobs:
       uses: actions/setup-node@v1
       with:
         node-version: ${{ matrix.node-version }}
-    - run: cd danfojs-node && yarn
-    - run: cd danfojs-node && yarn test:clean
-    - run: cd danfojs-browser && yarn
-    - run: cd danfojs-browser && yarn test:clean
+    - run: yarn test