Creating a group in proxy shape directly generates rotatePivot and scalePivot xformOps

**Describe the bug**

Whenever you create a group (Edit > Group or CTRL+G) the created `group` in the Maya USD Proxy Shape will directly show rotate and scale pivot xform ops in the channel box:


Whereas right clicking in the proxy shape in outliner and creating an "Xform" this does not happen.

**To Reproduce**
Steps to reproduce the behavior:

1. Create Maya USD Proxy
2. Create Cube Prim
3. Press CTRL+G

**Expected behavior**

If there's no pivot point opinion (e.g group options are set to 'Group Pivot' "origin") it should not really specify any pivot point related xform ops. Right?

That would leave things cleaner/lighter on the USD side of things. Only when adjusting the pivot should it set those xform ops?

**Screenshots**


**Used Software Versions**
- Maya: 2024.2
- Maya-USD: 0.27.0
- OS: Windows 10

**Additional context**
Side question:

Should we somehow improve the ordering of the attributes in channelBox for pivot points:


I think artists will be more familiar with Translate, Rotate, Scale first instead of pivots mixed in-between.
There does seem to be _some_ logic on how it sorts it because it does do translate, rotate, scale in that order which doesn't seem to come from the actual xformOpOrder.