Added codecov workflow (#42)

Author: edisdev

.github/workflows/ci.yml

@@ -37,4 +37,9 @@ jobs:
         run: echo "NODE_ICU_DATA=" >> $GITHUB_ENV
 
       - name: Run tests
-        run: yarn test:unit
+        run: yarn test:unit
+      
+      - uses: actions/checkout@master
+      - uses: codecov/codecov-action@v1
+        with:
+          files: ./coverage/coverage-final.json

.gitignore

@@ -25,4 +25,6 @@ yarn.lock
 package-lock.json
 
 # test
-coverage
+coverage/lcov-report
+coverage/clover.xml
+coverage/lcov.info