Create Issue Template

[FloorD]

Creates Issue Template to avoid issues or requests related to the CloudNativePG Docs.

Closes #373

[sxd]

@jsilvela What do you think about this?
@FloorD the DCO is failing

[jsilvela]

Asking out of unfamiliarity here: looking at the operator repo, the issue templates are configured with YAML, not markdown. And in the GH docs, I see only YAML examples, though they mention markdown.
If they do accept markdown, does it support Hugo style front matter?

[jsilvela]

Can we configure issue templates with markdown and a Hugo-style front matter?

[sxd]

Can we configure issue templates with markdown and a Hugo-style front matter?

What do you mean by "with markdown and a Hugo-style" ? I didn't got anything from the phrase :D

[jsilvela]

What I mean:
These lines at the top of the file issue-template.md are not proper markdown.

---
name: Issue template
about: 'Issue template for cloudnative-pg.io '
...
...

This is a custom format in Hugo to add metadata to blog posts. In hugo that section is called the front matter. See https://gohugo.io/content-management/front-matter/

So my question is: is this a format that will work in GitHub? To be honest I'd be surprised, but I have not set up issue templates, so I may be wrong.

[jsilvela]

In the GH documentation, I don't find anything about configuring the templates using markdown.
https://docs.github.com/en/communities/using-templates-to-encourage-useful-issues-and-pull-requests/configuring-issue-templates-for-your-repository#creating-issue-forms