showcase: baseHref and deployUrl were not replaced in some files during the latest release

[SuperITMan]

I'm submitting a...

[ ] Regression (a behavior that used to work and stopped working in a new release)
[X] Bug report  
[ ] Feature request
[ ] Documentation issue or request
[ ] Support request => Please do not submit support request here, instead see https://github.com/NationalBankBelgium/stark/blob/master/CONTRIBUTING.md#got-a-question-or-problem

Current behavior

The placeholders : <stark-dummy-base-href> and <stark-dummy-deploy-url> are not replaced after the build.

Expected behavior

The placeholders : <stark-dummy-base-href> and <stark-dummy-deploy-url> should be replaced after the build.

Minimal reproduction of the problem with instructions

Go on Stark showcase and look at the home page.
You'll see no image in the squares because the URL in the CSS is incorrect.

Environment

Angular version: 6.0.9
Stark version: 10.0.0-alpha.4