Updated default step_time in gen_turnaround

[mjrand]

Description

Updated the default step_time in gen_turnaround in turnarounds.py to step_time=0.1

Motivation and Context

This really should have been the default before probably. I think the ACU maxes out at 0.1s step time.
I think I had set this higher when I was testing very high accelerations.
This might be the cause of the az position errors seen on satp1, but that's uncertain until tested.
The high frequency may over constrain the turnaround or cause very strange ACU behavior if we're sending too many points.

How Has This Been Tested?

This has been tested before.

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)

Checklist:

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.

[BrianJKoopman]

Just a heads up -- I made some changes to the workflows/checks that run here today. You'll need to merge the latest main into this branch before proceeding.