Add XLAEnvironment plugin

[awaelchli]

What does this PR do?

Fixes #11321

Does your PR introduce any breaking changes? If yes, please list them.

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Make sure you had fun coding 🙃

cc @Borda @kaushikb11 @rohitgr7 @awaelchli @ananthsub

[akihironitta]

LGTM!