Update eslint from 5.2.0 to 5.3.0 (#22)

Author: dependencies[bot]

package-lock.json

@@ -42,7 +42,7 @@
   "homepage": "https://github.com/prettier-solidity/prettier-plugin-solidity#readme",
   "devDependencies": {
     "codecov": "^3.0.4",
-    "eslint": "^5.2.0",
+    "eslint": "^5.3.0",
     "eslint-config-airbnb": "^17.0.0",
     "eslint-plugin-import": "^2.13.0",
     "eslint-plugin-jsx-a11y": "^6.1.1",