Upgrade Prettier from 1.17 to 2.0.2.

Summary:
This gets us on the latest Prettier 2.x:
https://prettier.io/blog/2020/03/21/2.0.0.html

Notably, this adds support for TypeScript 3.8,
which introduces new syntax, such as `import type`.

Reviewed By: zertosh

Differential Revision: D20636268

fbshipit-source-id: fca5833d003804333a05ba16325bbbe0e06d6c8a

desktop/plugins/sections/index.js

@@ -35,7 +35,7 @@ import {
   DetailSidebar,
 } from 'flipper';
 
-const Waiting = styled(FlexBox)((props) => ({
+const Waiting = styled(FlexBox)(props => ({
   width: '100%',
   height: '100%',
   flexGrow: 1,
@@ -45,14 +45,14 @@ const Waiting = styled(FlexBox)((props) => ({
   textAlign: 'center',
 }));
 
-const InfoText = styled.div((props) => ({
+const InfoText = styled.div(props => ({
   marginTop: 10,
   marginBottom: 10,
   fontWeight: '500',
   color: colors.light30,
 }));
 
-const InfoBox = styled.div((props) => ({
+const InfoBox = styled.div(props => ({
   maxWidth: 400,
   margin: 'auto',
   textAlign: 'center',