Migrate from hash based routing

[pgayvallet]

The uptime app is currently using hashbang routing by having a BrowserRouter with an appRoute containing a hashbang suffix.

Hashbang routing is not supported by the Kibana Platform. The application's routing need to be migrated to leverage the ScopedHistory exposed to the plugins instead.

Related files:

kibana/x-pack/plugins/uptime/public/apps/plugin.ts

Lines 86 to 88 in 532f2d7

	core.application.register({
	appRoute: '/app/uptime#/',
	id: PLUGIN.ID,

kibana/x-pack/plugins/uptime/public/apps/uptime_app.tsx

Line 11 in 244ed04

import { BrowserRouter as Router } from 'react-router-dom';

kibana/x-pack/plugins/uptime/public/apps/uptime_app.tsx

Line 102 in 244ed04

<Router basename={routerBasename}>

[elasticmachine]

Pinging @elastic/uptime (Team:uptime)