chore: refresh lockfile (#300)

.travis.yml

@@ -8,7 +8,6 @@ before_install:
 - curl -o- -L https://yarnpkg.com/install.sh | bash
 - export PATH="$HOME/.yarn/bin:$PATH"
 - yarn global add greenkeeper-lockfile@1
-install: yarn --ignore-engines
 before_script: greenkeeper-lockfile-update
 script:
 - yarn commitlint --from="$TRAVIS_BRANCH" --to="$TRAVIS_COMMIT"

package.json

@@ -38,11 +38,11 @@
     "@babel/cli": "^7.4.4",
     "@babel/core": "^7.4.4",
     "@babel/preset-env": "^7.4.4",
-    "@commitlint/cli": "^8.0.0",
-    "@commitlint/config-conventional": "^8.0.0",
+    "@commitlint/cli": "^6.0.0",
+    "@commitlint/config-conventional": "^6.0.0",
     "babel-jest": "^24.8.0",
     "eslint": "^5.1.0",
-    "eslint-config-prettier": "^4.1.0",
+    "eslint-config-prettier": "^5.1.0",
     "eslint-plugin-eslint-plugin": "^2.0.0",
     "eslint-plugin-node": "^8.0.0",
     "eslint-plugin-prettier": "^3.0.0",