Bug#987070: reportbug: Support GNU BTS at debbugs.gnu.org

[Kevin Locke <kevin@kevinlocke.name>]

Package: reportbug
Version: 7.10.3
Severity: wishlist

Dear Maintainers,

It would be great if reportbug could be used to query and report bugs to
the debbugs-based GNU BTS at https://debbugs.gnu.org, presumably via
`-B gnu` or similar.

Thanks for considering,
Kevin

P.S. I started working on a patch to add support until I realized that
python3-debianbts only supports bugs.debian.org (Bug #949867), which may
make adding support difficult.