Initial CTRT update to Auto DevOps page
First MR to update the Auto DevOps page to meet CTRT guidelines, per technical-writing#579 (closed).
Overview of changes:
- Some general style edits.
- Move the content under
### How it works
into the introduction. - Add prerequisites to task topics.
- Move the content under
### Limitations
to more appropriate locations. - Reduce reading level to
7.71
.