Conversion to 4.0 doesn't change hex string to RGBA in Color constructor

[pattlebass]

Godot version

4.0.dev.dfdda9629

System information

Windows 10

Issue description

The way Godot parses hex Color strings is different in 4.0 (ARGB vs RGBA).

HEX string	Godot 3	Godot 4
00FFFFFF	Color(1,1,1,0)	Color(0,1,1,1)
0FFF	Color(1,1,1,0)	Color(0,1,1,1)

I think the project converter can look for the Color constructor and modify the string.
Something along the lines of /Color\("#?([a-fA-F0-9]{8}|[a-fA-F0-9]{4})"\)/gm.

Also, exported colors seem to reset their value because of an "@" in the tscn file. (@exported_color instead of exported_color)

Steps to reproduce

1. Open MRP in Godot 3 and look at output.
2. Upgrade the project using the conversion tool.
3. Open it in Godot 4 and notice how the colors are now totally different.

Minimal reproduction project

color_conversion.zip