Replace RegisterScreen with GeneralTextFieldDialog for player renaming

[bricealbiol]

Replace the full RegisterScreen with GeneralTextFieldDialog when renaming a player to match the UI used for grand prix and device configuration naming.
Issue #5338

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[Alayan-stk-2]

That might work, but it doesn't really simplify the renaming process and it adds additional code complexity, so I'm not quite convinced. I much prefer when the code is simplified.