Add Availability to change video rate

[MoElnaggar14]

Ticket

TICKET_NUMBER

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Pull Request Checklist

• [x] Resolved any merge conflicts
• [x] No build errors or warnings are introduced
• [x] New public methods have Documentation

Issue Summary

Change Speed Rate of video #113

Implementation Summary

• add setRate func in Player Protocol.
• implement setRate func

Reviewer Tips

• use setRate func to change the rate value of video.