Player variations installed to wrong Variations folder

Steps to reproduce:

1. Install 6000.7.0a2 via Hub with a CoreCLR Build Support module.
2. Try switching Scripting Backend to CoreCLR.
3. Editor reports it as not installed.

Actual results: Variations land in top-level Variations/; Editor reports CoreCLR as not installed.

Expected results: CoreCLR variations install to PlaybackEngines/MacStandaloneSupport/Variations/; backend recognized as installed.

Tested on (OS): 

• MacOS

Notes:

• move all folders under <EditorRoot>/Variations/ into <EditorRoot>/PlaybackEngines/MacStandaloneSupport/Variations/; restart Editor. Confirmed fixes it.
• Not tested on Linux or Windows OS.
• Linux and Windows player/server support variations (installed on macOS host) also end up in the top-level Variations/ folder.