Remove load_step from the tscn file format

[MartinDelille]

I propose to remove the load_step tag stored in the tscn files that make versioning the project tedious, especially during rebase.

Let's take an example where I commit changes to the main.tscn file:

• the first change increase the load_step go from 3 to 5
• the second change increase the load_step from 5 to 6.

If I decide to reorder this two commits, I will have a conflict on the load step value and will have to manually set it.

In the current draft I did here here I propose a simple removal. It has a drawback that the progress won't be displayed properly, which is fine for my Godot fork.

I could eventually restore the feature by parsing the whole file to pre compute the resources_total value.

I'd like to have the team feedback on this change before I proceed.

[dsnopek]

There's a pre-existing proposal for this (which has some support): #11802

[MartinDelille]

Ok I closed. I mispelled during the search so I didn't found it.