Remove per-file progress reporting when exporting to Android

Created by: Calinou

Calling step() on EditorProgress too often will slow down the rest of the editor, so it's best avoided. This is also more consistent with other exporters, as most of them don't report per-file progress either.

Exporting a 2D project with ~1,100 files to Android now takes about 10 seconds from a debug editor build instead of 65 seconds.

This closes #30850 (closed).