fix: update webGLContextAttributes powerPreference type

[forforfos]

This PR is an addition to #543

It updates the Type of the powerPreference attribute from the unityConfig object webglContextAttributes.

This attribute accepts the values of 0, 1 and 2 instead of 'default', 'low-power' and 'high-performance'.

[forforfos]

@jeffreylanters
Hello!
I was wondering if there is something missing so as to merge this PR.

[jeffreylanters]

Excuse me @forforfos, I've had a lot going on privately, so release the PR was delayed a bit. I'll merge and release it this week. Thanks for checking with me! 🙌🏼

[jeffreylanters]

Released in https://github.com/jeffreylanters/react-unity-webgl/releases/tag/v9.5.1

Thanks for your contribution!

[forforfos]

Excuse me @forforfos, I've had a lot going on privately, so release the PR was delayed a bit. I'll merge and release it this week. Thanks for checking with me! 🙌🏼

No worries friend! I was just wondering if I was missing something to complete the PR!

Thank you very much for your time and feedback! <3

On a separate matter, if you have time, check this out at some point! #544 I would really like to implement it, and it is really fast and easy I think!

kisses