pip for role anonymizer

[KannarFr]

PIP for #23386

[github-actions]

@KannarFr Please add the following content to your PR description and select a checkbox:

- [ ] `doc` <!-- Your PR contains doc changes -->
- [ ] `doc-required` <!-- Your PR changes impact docs and you will update later -->
- [ ] `doc-not-needed` <!-- Your PR changes do not impact docs -->
- [ ] `doc-complete` <!-- Docs have been already added -->

[lhotari]

PIP-385 is already taken.

Please find another available PIP. The current way to find an available PIP is to search on the dev mailing list discussions whether there's a conflict with the picked PIP number. The first one to open the discussion about the PIP "wins".

You should also make the PR title match the way that we use
[feat][pip] PIP-XXX: Role Anonymizer for Pulsar Logging would be the way to name the PR. Start the thread on the dev mailing list asap after assigning the PR number so that you "win" the possible race condition in assigning the PIP number.

[lhotari]

At the current moment, PIP-393 is the next available PIP number.
Here's the search: https://lists.apache.org/[email protected]:lte=1y:PIP-393

I first looked at https://lists.apache.org/[email protected] and then started incrementing the PIP number until there were no search matches. That's how you find an available PIP number.

You could also check if someone has already created a PR with PIP-393 with this query "is:pr in:title PIP-393"
https://github.com/apache/pulsar/pulls?q=is%3Apr+in%3Atitle+PIP-393

That's the reason also why you should follow the current conventions for starting the thread and for naming the PR for the PIP. We should include the proper steps in the PIP README so that it's clear to everyone how the PIP number gets assigned in practice.

Here's a good example of how to start the discussion thread: https://lists.apache.org/thread/9wddmj4o5mrdst427r40rr7phqb05y6s
And after the discussion, starting the voting thread:
https://lists.apache.org/thread/p4zvok4l6dxrm0hqbno5s21tq4s33f7s
There will soon be an example of closing the voting thread there.