startplasma-wayland: Don't set GDK_SCALE and GDK_DPI_SCALE
We did this to work around a bug whereby envars would be inappropriately propagated when going from X11 to Wayland, causing GTK apps to be scaled to too large a size.
However this no longer appears to be an issue with any of the GTK apps I tested (Blanket, Bustle, Cheese, Chromium, Firefox, Gedit, GIMP, GNOME Sudoku, Inkscape, Peek, Video Downloader), and keeping it causes a bug whereby non-GTK XWayland apps that perhaps inappropriately look at these envars to determine their scale are scaled too small.
This hack has outlived its usefulness; let's kill it.
BUG: 443215 FIXED-IN: 5.26.3
Edited by Nate Graham