fix: remove extra parentheses with spec test

[liamdebeasi]

resolves #489

There was an extra set of parentheses that was causing tests to fail on a syntax error.

Error: src/app/pages/home/home.page.spec.ts:8:14 - error TS2304: Cannot find name 'async'.

8   beforeEach(async(() => {
               ~~~~~

This was probably left over from our previous waitForAsync usage which was a function call:

angular-toolkit/packages/schematics/component/files/__name@dasherize@if-flat__/__name@dasherize__.__type@dasherize__.spec.ts.template

Line 10 in 6f5cc26

beforeEach(waitForAsync(() => {