Missing redirect to fix link breaking from issues bug report to reproduction page in docs

[reregaga]

Description

In the old bug reports, the link to the page in the documentation with instructions on how to create a minimal reproduction goes to a 404 page. I do not know if the link recently has been updated in issues too with 87fed7e , so just in case I decided to write about it.

Related links

• Old issue for example:
  Sometimes toc.follow doesn't move last entries into view #4960

• Old link from old issues (return 404):
  https://squidfunk.github.io/mkdocs-material/contributing/reporting-a-bug/reproduction/
  See:

  I have attached a .zip file with a minimal reproduction.

• New page (200):
  https://squidfunk.github.io/mkdocs-material/contributing/reporting-a-bug/#reproduction

• It seems that the link to the new documentation has not yet been updated in the template to create issues:
  https://github.com/squidfunk/mkdocs-material/issues/new?assignees=&labels=&template=01-report-a-bug.yml
  See:

  I have attached a .zip file with a minimal reproduction.

Proposed change

• Update the template for issues.
• It would be good to organize redirect from old link to new one, for those who can use old link while reading old issues.

Before submitting

• I have read and followed the documentation issue reporting guidelines.
• I have attached the links to the described sections of the documentation

[katharinalisalin]

Thanks for reporting! Fixed in 83468bc and 2e689f0.