feat: Initial E2E test framework for v2 (#288)

This brings an initial E2E test (really, an integration test - it's only running the server locally, as opposed to against a deployment - but it'd be easy to point playwright to a deployment).

Demo gif:
![test2](https://user-images.githubusercontent.com/88213859/156078517-6cb4ef84-337b-4e16-a8bc-aea7d06dcbcb.gif)

This test exercises a minimal flow for login:
- Run the `coderd` binary to start a server on 3000
- Create an initial user as part of setup
- Go through the login flow and verify we land on the projects page

It will be useful to have to ensure that #360 doesn't introduce a regression in the login flow

Future E2E tests that would be useful:
- Create a project & verify it shows in the UI
- Create a workspace and verify it shows in the UI

site/package.json

@@ -12,6 +12,9 @@
     "format:write": "prettier --write '**/*.{css,html,js,json,jsx,md,ts,tsx,yaml,yml}' && sql-formatter -l postgresql ./database/query.sql -o ./database/query.sql",
     "lint": "jest --selectProjects lint",
     "lint:fix": "FIX=true yarn lint",
+    "playwright:install": "playwright install",
+    "playwright:install-deps": "playwright install-deps",
+    "playwright:test": "playwright test --config=e2e/playwright.config.ts",
     "storybook": "start-storybook -p 6006 -s ./static",
     "storybook:build": "build-storybook",
     "test": "jest --selectProjects test",
@@ -21,6 +24,7 @@
     "@material-ui/core": "4.9.4",
     "@material-ui/icons": "4.5.1",
     "@material-ui/lab": "4.0.0-alpha.42",
+    "@playwright/test": "1.17.2",
     "@react-theming/storybook-addon": "1.1.5",
     "@storybook/addon-actions": "6.4.19",
     "@storybook/addon-essentials": "6.4.19",