[Date-Time-Picker] Month/Year changing redundant announcement fix

[ashishkumbhare116]

Summary

Currently when navigating through the Date Picker popup and selecting a value for "Month"/ "Year", will only expose the selected value. But, the selected value is getting exposed twice as "February, Month Combobox February", .

What was changed:

Why it was changed:

Testing

This change was tested using:

• WDIO
• Jest
• Visual testing (please attach a screenshot or recording)
• Other (please describe below)
• No tests are needed

Reviews

In addition to engineering reviews, this PR needs:

• UX review
• Accessibility review
• Functional review

Additional Details

This PR resolves:

UXPLATFORM-XXXX

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[sugan2416]

Announcing once as expected

[SwethaM03]

+1
As per PR, the issues are fixed and working as expected. However when the drop down is expanded for month and year combobox, the instruction to use the arrow keys are read out for each option present in the dropdown which is incorrect.
And I observed that 'Open Calendar' button name getting announced multiple times while navigating to the Calendar button.