fix: missing BrowserModule.withServerTransition

[justindujardin]

Without this, angular throws a helpful error while serving the page:

Unhandled Promise rejection: renderModule[Factory]() requires the use of BrowserModule.withServerTransition() to ensure
the server-rendered app can be properly bootstrapped into a client app. ; Zone: <root> ; Task: Promise.then ; Value: { Error: renderModule[Factory]() requires the use of BrowserModule.withServerTransition() to ensure
the server-rendered app can be properly bootstrapped into a client app.
    at new Error (native)
    at Error.v (/Users/coolpath/ng-universal-demo/dist/main.js:251:2215)
    at /Users/coolpath/ng-universal-demo/dist/main.js:155:16564
    at e.invoke (/Users/coolpath/ng-universal-demo/dist/main.js:251:8988)
    at n.run (/Users/coolpath/ng-universal-demo/dist/main.js:251:4723)
    at /Users/coolpath/ng-universal-demo/dist/main.js:251:1787
    at e.invokeTask (/Users/coolpath/ng-universal-demo/dist/main.js:251:9672)
    at n.runTask (/Users/coolpath/ng-universal-demo/dist/main.js:251:5372)
    at o (/Users/coolpath/ng-universal-demo/dist/main.js:251:499)
    at Server.invoke (/Users/coolpath/ng-universal-demo/dist/main.js:251:10588)
    at emitTwo (events.js:106:13)
    at Server.emit (events.js:191:7)
    at HTTPParser.parserOnIncoming [as onIncoming] (_http_server.js:546:12)
    at HTTPParser.parserOnHeadersComplete (_http_common.js:99:23)
...

[robwormald]

👍

[usernamealreadyis]

#6