ENH: use github issue form for doc improvement
xref #42951, #43009

Screenshot of current version: 
<img width="829" alt="Screen Shot 2021-08-21 at 12 12 44 PM" src="https://user-images.githubusercontent.com/37011898/130328264-29ea829e-b664-4a68-bb7d-8a3b21c5bfee.png">


https://github.com/mzeitlin11/issue-forms/issues if anyone wants to play around with opening issues with the form.