fix(ModalPage): add css variable to set top and right position

[abdmmar]

Description

Add CSS Variable to be able set top and right position for ModalPage component.

• --modal-page-close-btn-right for setting close button right position, default to 32px
• --modal-page-close-btn-top for setting close button top position, default to 32px

Since we already have top and right position, setting position using margin is unnecessary

Usage

In the application, we can redeclare the CSS Variable like this:

.modal {
  --modal-page-close-btn-top: 50px
}

[rayhan-ab]

if it's a fix, shouldn't it be #patch instead of #minor?