Requests: Scene collection and profile name checking

[tt2468]

Description

For SetCurrentProfile and SetCurrentSceneCollection, check if it exists before attempting to switch to it, and return an error if it does not exist.

Motivation and Context

Because the code told me to

How Has This Been Tested?

Tested OS(s): Ubuntu 20.04

Types of changes

• Enhancement (modification to a current event/request which adds functionality)

Checklist:

• I have read the contributing document.
• My code is not on the master branch.
• The code has been tested.
• All commit messages are properly formatted and commits squashed where appropriate.
• I have included updates to all appropriate documentation.