[Chapel Merge] Add .gitignore entries for some developer and test

Branch: refs/heads/main
Revision: 05dd77a
Author: gbtitus
Link: Unavailable
Log Message:

Merge pull request #19406 from gbtitus/moreIgns

Add .gitignore entries for some developer and test stuff.

(Reviewed by @mppf.)

The util/chplenv python cache, the compiler-internals symbolic
link used in building docs, and a couple of things left behind by
dyno testing.

Modified Files:
A doc/rst/developer/.gitignore

A test/dyno/primers/.gitignore
A test/dyno/primers/chplvis/.gitignore
A util/chplenv/.gitignore

Compare: https://github.com/chapel-lang/chapel/compare/4c98fd3ac119...05dd77af226f