Replace issue templates with issue forms [SDK-4168]

[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

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

[Widcket]

The path /c/sdks/auth0js/59 no longer exists.

[stevehobbsdev]

Please include the question "Which browsers have you tested in", which is on the original bug report. Not sure if it would be too restrictive to have a drop-down list with the major ones in case they're using something obscure, will leave that up to you.

[Widcket]

Please include the question "Which browsers have you tested in", which is on the original bug report. Not sure if it would be too restrictive to have a drop-down list with the major ones in case they're using something obscure, will leave that up to you.

Sure thing, added in 4b32d2c (I used the browsers in https://gs.statcounter.com/browser-market-share/desktop/worldwide). Copy-paste mishap, because this field is not present in another browser library I did previously: https://github.com/auth0/lock/blob/master/.github/ISSUE_TEMPLATE/report_a_bug.md#environment.

[stevehobbsdev]

No worries, thanks. I think that change can/should be present in all the browser-based JS libraries (including Lock) but I can help roll it out as I see them 👍🏻

[Widcket]

Added it to the lock PR as well: auth0/lock#2324