checks: Check for game captures needing admin

[Penwy]

Description

Some games require OBS to be run as admin for game capture to capture them properly, usually because they themselves are running as admin.
This usually manifests in the log with the line [game-capture: '<source name>'] could not open process: <executable>
This PR leverages this to present the user with a message informing them that running obs as admin might be needed.

To be noted, I have hesitations and would like feedback on two points of its presentation, namely, the title of the factoid, and whether listing the executables would really be useful to the user.

Motivation and Context

"Game capture no work" is not only one of the most common issues in windows support, it is also a quite obscure one. There are multiple potential causes for it, which are indistinguishable without reading the log file with special knowledge of it.
This would allow to lift this obscurity to end users on one of the possible causes.

How Has This Been Tested?

Running locally with https://obsproject.com/logs/1EHNwuIInbVRKWxI, as well as a modified version of it to check for behaviour in case of multiple executable.

Types of changes

• New feature (non-breaking change which adds functionality)

Checklist:

• My code has been run through clang-format.
• 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.

[Fenrirthviti]

I need to mull over the verbiage here, but conceptually this seems fine.

I just want to be sure that it's clear admin may not resolve the issue and there might be something else going on. I thought we had a list of known games that do require admin rights, but I suppose this message is very unlikely to show up otherwise, so it's probably fine.

EDIT: for reference: https://github.com/obsproject/obs-studio/blob/master/plugins/win-capture/data/compatibility.json

[Penwy]

For the wording, I could add a link to the Game capture troubleshooting page on the KB?
Has the advantages of listing the other avenues for a solution.

[Fenrirthviti]

I think that's a good idea, yeah. Something like:

Game Capture was unable to capture the selected window. This may be solved by running OBS as an Administrator. For more info, see our [Game Capture Troubleshooting] guide.