Add hold last frame option in recorder docker export dialog

In the Recorder docker export dialog add a "Hold Last frame" option to repeat the last frame for a user defined amount of seconds on export. Useful for you/viewers to actually see the completed work at the end of the video instead of the video ending immediately. Defaults to 5 seconds

The default "render as" profiles have been edited to support the new option. If repeating the last frame is undesired then setting "Hold Last Frame" to 0 adds no additional frames.

BUG:441184

Test Plan

1. Open the recorder docker and export a video (Should add a default 5 seconds to end of clip)
2. Try 0 seconds for "hold last frame option" and export (Should not add any frames at end of clip)

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