Make sure test runs have the most up to date assets
Make sure test runs have the most up to date assets

- All gulp tasks going forward need to declare dependencies and return a stream

[Finishes #79616300]

Signed-off-by: Nicole Sullivan <4ab7e2960369063855aad4ef791fa27066322d72@pivotal.io>

sjolicoeur/pivotal-ui,CanopyCloud/pivotal-ui,npm/pivotal-ui,npm/pivotal-ui,CanopyCloud/pivotal-ui,npm/pivotal-ui,sjolicoeur/pivotal-ui,CanopyCloud/pivotal-ui,pivotal-cf/pivotal-ui,sjolicoeur/pivotal-ui,sjolicoeur/pivotal-ui,pivotal-cf/pivotal-ui,pivotal-cf/pivotal-ui