[Typescript, Grid] Rule justify-xs-space-evenly does not exist on type GridClassKey in overrides.d.ts

[Rikpat]

• I have searched the issues of this repository and believe that this is not a duplicate.

Summary

Rule justify-xs-space-evenly in MuiGrid overrides doesn't exist in Typescript declaration file despite it being in documentation and implementation working.
I could create a PR myself to just add a new variant for the property, but I don't know if this isn't a deeper issue of typescript types not being generated, or if there's more of them missing.

This is my first issue, I hope it's up to standards.

[mbrookes]

@Rikpat The type definitions aren't generated, so feel free to submit a PR.

[Rikpat]

I've created a PR #19050