Add a developer task issue template (#17769)
Summary of the issue:
* We regularly need to create issues to track developer facing changes, but we do not have a good issue template for that.
* https://github.com/nvaccess/nvda/issues/new/ no longer uses .github\ISSUE_TEMPLATE.md when we disable blank issues. So we should remove it.
* The new issue experience allows types of issues (e.g. bug, feature, task), we should use them for our issue templates
Description of user facing changes:
None
Description of development approach:
* Add an issue template for dev changes
* Remove redundant blank issue template
* add issue types to templates
