feat(ion-modal): break point class & values

[rbalet]

Prerequisites

• I have read the Contributing Guidelines.
• I agree to follow the Code of Conduct.
• I have searched for existing issues that already include this feature request, without success.

Describe the Feature Request

Add the breakpoint as a class name of the ion-modal.

Describe the Use Case

As my app use border-radius, I had to apply the same to the modal to keep it consistent.

But when the modal it at the 1 breakpoint, I would like to remove the border-radius.

Describe Preferred Solution

having a breakpoint-[value] class name, which will contain the value of the different possible breakpoint

Describe Alternatives

Also possible to have only if the ion-modal is actually overflowing or not

nativeElement.scrollHeight > nativeElement.clientHeight

Related Code

I could propose a PR if wished

Additional Information

No response