Add snapshot methods for Light and Dark mode screens

[steve509]

Hello 👋,

I work on a project that supports both Light and Dark mode and thought it would be nice to take snapshot references of views in different themes. This PR adds a few helper methods to accomplish that. Any feedback would be appreciated.

Cheers,
Steve

[CLAassistant]

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1 out of 2 committers have signed the CLA.

✅ steve509
❌ Steve Tran

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[k0nserv]

@steve509 Can you sign the CLA so this can be merged?

[steve509]

I'm going to re-open this to fix the CLA check.

[steve509]

Reopened here: #125

If you don't mind taking a look again, thanks!