fix(datepicker): webkit-related stylings

[KenLSM]

Problem

On mobile phones and safari, the text input for DatePicker

• affects only <DatePicker />, other <Input />-related fields are not affected
• affects specifically when component is disabled

• text is set to gray but appears to be whitish-grey on chrome mobile, and safari browsers

Closes FRM-1473

Solution

• Took reference from design-system and extracted aria fields and moved them down into the child components.
• Fixed missing borderRightRadius on <CalendarButton />

Ideally, we should migrate to use design-system so that we don't have to patch issues like this.

Breaking Changes

• No - this PR is backwards compatible

Before & After Screenshots

Location/Modifier	Before	After
Active
Filled
Error
Disabled
Admin
Admin Active
Admin Hover
Admin Error

Tests

Regression Tests

• Ensure that DatePicker fields cannot be interacted when field is disabled
• Ensure that DatePicker fields cannot be selected with Tab when field is disabled
• Ensure that DatePicker input field is visible when viewed from Safari browser when field is disabled

[linear]

FRM-1473 Bug: MyInfo Child DOB not showing up in mobile FE

Zendesk ticket

[wanlingt]

lgtm thanks for fixing this!!