[Enhancement] Replace the fullscreen button image of media element with font icons

[mhrastegari]

Summary

Since full screen button of media element is only on Windows (10/11) we can use its native icons (Segoe MDL2 Assests/Segoe Fluent Icons) so easily.
And also I'm up for doing a PR :)

Screenshots

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[mhrastegari]

I'll close this since there's a PR for it :)

#1868