Update ISSUE_TEMPLATE.md
Update ISSUE_TEMPLATE.md

Elaborating the issue template a bit more. Specifically, trying to avoid people from putting `latest` in the VSCodeVim version.
westim/Vim,VSCodeVim/Vim,Chillee/Vim,Chillee/VSCodeNeovim,VSCodeVim/Vim,Chillee/VSCodeNeovim,westim/Vim,Chillee/Vim,Chillee/VSCodeNeovim,westim/Vim