Update formiojs version to 4.19.0

[wadeV12]

In the latest stable version of @formio/angular 7.0.0 we have a hard dependency on formiojs styles here:

https://github.com/formio/angular/blob/v7.0.0/projects/angular-formio/src/components/formio/formio.component.ts#L11

It means that it doesn't matter which formiojs version I will use as a peer dependency in my project I will still get a styles from a version specified in your repository and they will be inlined in the FormioComponent during build time.

https://github.com/formio/formio.js/pull/5447

I have this issue in my project and the long-term fix could probably be a separate loading of styles and not inlining them but so far package update may also work fine (as the local style override...but override does not look like the best solution).