Match xplat/yoga/javascript prettier conventions

Summary:
Match Prettier config to match other Meta OSS projects

Didn't update the test generator to use this form yet.

Reviewed By: yungsters

Differential Revision: D45570415

fbshipit-source-id: d5fd791b047debf41c28aecac75fb8dde16da3e3

javascript/.prettierrc.js

@@ -8,8 +8,9 @@
  */
 
 module.exports = {
-  trailingComma: "es5",
-  tabWidth: 2,
-  semi: true,
-  singleQuote: false,
+  arrowParens: 'avoid',
+  bracketSameLine: true,
+  bracketSpacing: false,
+  singleQuote: true,
+  trailingComma: 'all',
 };