### Godot version

8449592d92eaeef990f5502b419d491ee3eeb7a6

### System information

Windows 11

### Issue description

Zooming in the script editor on an empty script freezes the entire editor for a few seconds, but if the file is large then it freezes for 4-5 seconds (which is unacceptable). Looks like a recent regression.

### Steps to reproduce

Just zoom in/out on the large script file.

### Minimal reproduction project

N/A
ERR_FAIL_INDEX((int)p_spacing, 4);
	FontFallback *fd = font_owner.get_or_null(p_font_rid);
	ERR_FAIL_COND(!fd);
	MutexLock lock(fd->mutex);
	if (fd->extra_spacing[p_spacing] != p_value) {
		_font_clear_cache(fd);
		fd->extra_spacing[p_spacing] = p_value;
	}
}
int64_t TextServerFallback::_font_get_spacing(const RID &p_font_rid, SpacingType p_spacing) const {
	ERR_FAIL_INDEX_V((int)p_spacing, 4, 0);
	FontFallback *fd = font_owner.get_or_null(p_font_rid);
	ERR_FAIL_COND_V(!fd, 0);
	MutexLock lock(fd->mutex);
	return fd->extra_spacing[p_spacing];
}
void TextServerFallback::_font_set_transform(const RID &p_font_rid, const Transform2D &p_transform) {
	FontFallback *fd = font_owner.get_or_null(p_font_rid);
	ERR_FAIL_COND(!fd);
	MutexLock lock(fd->mutex);
	if (fd->transform != p_transform) {
		_font_clear_cache(fd);
		fd->transform = p_transform;
	}
}
Transform2D TextServerFallback::_font_get_transform(const RID &p_font_rid) const {