Remove DPI detection for default SCALE

This often leads to `SCALE` values that are way off, and makes Lite XL 
unusable, so we now just default it to 1.

data/core/start.lua

@@ -2,7 +2,7 @@
 VERSION = "@PROJECT_VERSION@"
 MOD_VERSION = "3"
 
-SCALE = tonumber(os.getenv("LITE_SCALE") or os.getenv("GDK_SCALE") or os.getenv("QT_SCALE_FACTOR")) or SCALE
+SCALE = tonumber(os.getenv("LITE_SCALE") or os.getenv("GDK_SCALE") or os.getenv("QT_SCALE_FACTOR")) or 1
 PATHSEP = package.config:sub(1, 1)
 
 EXEDIR = EXEFILE:match("^(.+)[/\\][^/\\]+$")