tray: load_icon use request_size directly

[akliuxingyuan]

I delete tmp_size part, when call load_icon function, use request_size icon_size * image.get_scale_factor() like wlr/taskbar
get_icon_sizes doesn't handle scaling, if icon isn't scalable, tmp_size will be smaller size

Waybar/src/modules/wlr/taskbar.cpp

Lines 181 to 184 in 1149e51

	auto scaled_icon_size = size * image.get_scale_factor();
	try {
	pixbuf = icon_theme->load_icon(ret_icon_name, scaled_icon_size, Gtk::ICON_LOOKUP_FORCE_SIZE);

for example: nm-applet

[archseer]

I think this ruined scaling on my bar for certain icons: They used to be the same size, but now the volume icons, the first workspace icon and the CPU icon are slightly smaller than the rest. I'm using Font Awesome for all of them.

[archseer]

Hmm maybe not since the icons are a part of the font, not a separate image. I need to do a bisect from the last release