Add new Jinja filters

[nicholasmhughes]

What does this PR do?

Adds access to some itertools functions, a list flattener, and a filter to turn dictionaries into Salt state parameters (a list of single-key dictionaries).

What issues does this PR fix or reference?

Fixes: #61502

Merge requirements satisfied?

[NOTICE] Bug fixes or features added to Salt require tests.

• Docs
• Changelog - https://docs.saltproject.io/en/master/topics/development/changelog.html
• Tests written/updated

Commits signed with GPG?

Yes

Please review Salt's Contributing Guide for best practices.

See GitHub's page on GPG signing for more information about signing commits with GPG.

[nicholasmhughes]

re-run pr-debian-9-amd64-py3-pytest

[waynew]

Generally I'm +1 here - just one question about recursion...

[github-actions]

Hi! I'm your friendly PR bot!

You might be wondering what I'm doing commenting here on your PR.

Yes, as a matter of fact, I am...

I'm just here to help us improve the documentation. I can't respond to
questions or anything, but what I can do, I do well!

Okay... so what do you do?

I detect modules that are missing docstrings or "CLI Example" on existing docstrings!
When I was created we had a lot of these. The documentation for these
modules need some love and attention to make Salt better for our users.

So what does that have to do with my PR?

I noticed that in this PR there are some files changed that have some of these
issues. So I'm leaving this comment to let you know your options.

Okay, what are they?

Well, my favorite, is that since you were making changes here I'm hoping that
you would be the most familiar with this module and be able to add some other
examples or fix any of the reported issues.

If I can, then what?

Well, you can either add them to this PR or add them to another PR. Either way is fine!

Well... what if I can't, or don't want to?

That's also fine! We appreciate all contributions to the Salt Project. If you
can't add those other examples, either because you're too busy, or unfamiliar,
or you just aren't interested, we still appreciate the contributions that
you've made already.

Whatever approach you decide to take, just drop a comment here letting us know!

Detected Issues (click me)

Check Known Missing Docstrings...........................................Failed
- hook id: invoke
- duration: 1.41s
- exit code: 1
The function 'jinja_raise' on 'salt/utils/jinja.py' does not have a docstring

The function 'regex_escape' on 'salt/utils/jinja.py' does not have a docstring

The function 'method_call' on 'salt/utils/jinja.py' does not have a docstring

The function 'show_full_context' on 'salt/utils/jinja.py' does not have a docstring

Found 4 errors

---

Thanks again!

[Ch3LL]

@waynew can you re-review please?