Bump codecov from 2.3.1 to 3.1.0

Bumps [codecov](https://github.com/codecov/codecov-node) from 2.3.1 to 3.1.0.
- [Release notes](https://github.com/codecov/codecov-node/releases)
- [Commits](codecov/codecov-node@v2.3.1...v3.1.0)

Signed-off-by: dependabot[bot] <support@dependabot.com>

Author: dependabot-support

package-lock.json

@@ -39,7 +39,7 @@
   "devDependencies": {
     "codacy-coverage": "^2.1.0",
     "code": "^4.1.0",
-    "codecov": "^2.3.1",
+    "codecov": "^3.1.0",
     "eslint": "^5.12.1",
     "eslint-config-google": "^0.8.0",
     "husky": "^0.14.1",