Replace issue templates with issue forms [SDK-4166]

[Widcket]

Changes

This PR replaces the Markdown-based issue templates with issue forms. These forms are a direct conversion of the Markdown issue templates, with the addition of a checklist at the top containing links to self-serve resources.

Checklist

• [X] I have read the Auth0 general contribution guidelines
• [X] I have read the Auth0 Code of Conduct
• [X] All existing and new tests complete without errors