Add docstring for Mobject.rotate and Rotating class

[irvanalhaq9]

Overview: What does this pull request change?

Adding detailed docstrings for the Mobject.rotate, also add docstring for Rotating class.

Breaking change:
This PR also renames the radians parameter to angle and reorders the arguments in the Rotating class to be consistent with the Mobject.rotate and the Rotate class.
Before: Rotating(mobject, axis, radians, ...)
After: Rotating(mobject, angle, axis, ...)

Links to added or changed documentation pages

1. rotate: https://manimce--4147.org.readthedocs.build/en/4147/reference/manim.mobject.mobject.Mobject.html#manim.mobject.mobject.Mobject.rotate
2. Rotating: https://manimce--4147.org.readthedocs.build/en/4147/reference/manim.animation.rotation.Rotating.html#manim.animation.rotation.Rotating

Reviewer Checklist

• The PR title is descriptive enough for the changelog, and the PR is labeled correctly
• If applicable: newly added non-private functions and classes have a docstring including a short summary and a PARAMETERS section
• If applicable: newly added functions and classes are tested