fix(datetime): time button is easier to access with screen readers

[sean-perkins]

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)
  • Some docs updates need to be made in the ionic-docs repo, in a separate PR. See the contributing guide for details.
• 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):

What is the current behavior?

When screen readers announce the datetime body, the previous (not visible), current (visible) and next month (not visible) are announced.

Issue URL: Internal

What is the new behavior?

• Only the working month (current month) is announced to screen readers
• Focus can be easily moved to the time picker (if enabled), or outside of the calendar body

Does this introduce a breaking change?

• Yes
• No

Other information

Split from: #25980

[liamdebeasi]

Great job! Can we update the commit title to something more descriptive of the fix? The working month has always been announced by screen readers. Maybe something like fix(datetime): time button is easier to access with screen readers or fix(datetime): swiping with screen reader no longer incorrectly changes month