fix(schematics): use Angular default properties when not defined

[timdeschryver]

PR Checklist

Please check if your PR fulfills the following requirements:

• The commit message follows our guidelines: https://github.com/ngrx/platform/blob/master/CONTRIBUTING.md#commit
• Tests for the changes have been added (for bug fixes / features)
• Documentation has been added / updated (for bug fixes / features)

PR Type

What kind of change does this PR introduce?

[x] Bugfix
[ ] Feature
[ ] Code style update (formatting, local variables)
[ ] Refactoring (no functional changes, no api changes)
[ ] Build related changes
[ ] CI related changes
[x] Documentation content changes
[ ] Other... Please describe:

What is the current behavior?

Closes #1036(comment)

What is the new behavior?

Does this PR introduce a breaking change?

[ ] Yes
[x] No

Other information

By removing the default values in the schema, we can remove the undefined values before we pass them to the Angular component schematic. By doing this, Angular will replace the undefined values with the defaults set in angular.json. If no default value is provided in the angular.json file, it will use the defaults from the Angular schematic schema.

I tried to write a test for it but it seems like during the tests, the transformer isn't included.