Bump ECMAScript version in ESLint config
diff --git a/.eslintrc.js b/.eslintrc.js
index a82fcb9..8baadfb 100644
--- a/.eslintrc.js
+++ b/.eslintrc.js
@@ -10,7 +10,7 @@
   },
   parser: 'babel-eslint',
   parserOptions: {
-    ecmaVersion: '2018',
+    ecmaVersion: '2019',
   },
   plugins: ['import', 'prettier'],
   rules: {