Fixing Yarn issue in CI (#528)

* Update config.yml

* Update config.yml

* Update package.json

* Update config.yml

Author: alyezz

.circleci/config.yml

@@ -20,7 +20,7 @@ jobs:
       - restore_cache:
           key: node-v1-{{ checksum "package.json" }}-{{ arch }}
 
-      - run: yarn install
+      - run: yarn
 
       - save_cache:
           key: yarn-v1-{{ checksum "yarn.lock" }}-{{ arch }}
@@ -90,7 +90,7 @@ jobs:
     steps:
       - checkout:
           path: ~/project
-      - run: yarn install
+      - run: yarn
       - run:
           name: chmod permissions
           command: cd android && chmod +x ./gradlew

package.json

@@ -34,7 +34,7 @@
   "devDependencies": {
     "babel-core": "7.0.0-bridge.0",
     "babel-jest": "^24.8.0",
-    "codecov": "^3.7.0",
+    "codecov": "~3.7.0",
     "jest": "^24.8.0",
     "metro-react-native-babel-preset": "0.51.1",
     "react": "^16.8.6",