Add good Issue/PR checklists

[pavithraes]

Originally from @jaimergp in #75:

I think the text would benefit from a little section on how to write good issues and/or pull request descriptions. Some projects might not enforce it but it's good citizenship to leave a papertrail of the context of the contribution, and backreferencing as needed. Of course, if the project has some guidelines, follow them, but in the absence of them, we can still strive to provide good examples of useful interactions (specially when doing git-archeology in the future!).

We can add a couple of checklists for authoring issues and PRs in this section:
https://github.com/chanzuckerberg/czi-oss-training/blob/main/02-participating-in-oss/04-contributing-tips.md#getting-the-most-of-the-issue-trackers-