fix(ng-add): Fix path for css styles in monorepo

[eduardoRoth]

Pull request checklist

Please check if your PR fulfills the following requirements:

• Tests for the changes have been added (for bug fixes / features)
• Docs have been reviewed and added / updated if needed (for bug fixes / features)
• Build (npm run build) was run locally and any changes were pushed
• Lint (npm run lint) has passed locally and any fixes were made for failures

Pull request type

Please check the type of change your PR introduces:

• Bugfix
• Feature
• Code style update (formatting, renaming)
• Refactoring (no functional changes, no api changes)
• Build related changes
• Documentation content changes
• Other (please describe): ng add schema updated to handle multiple applications project structure

What is the current behavior?

When you run ng add @ionic/angular --project=name, the variables.css file is created but it's path in angular.json is wrong, so you need to update it manually

Issue Number: N/A

What is the new behavior?

Added a new option to the schema:

ng add @ionic/angular --project=my-project --root=apps

It'll update the angular.json file to point the variables.css file to apps/my-project/src/theme/variables.css

Does this introduce a breaking change?

• Yes
• No

Other information

[eduardoRoth]

@mhartington @SchnWalter just updated the code with your suggestions.

[mhartington]

LGTM!