Bug#995910: gitaly: unsatisfiable build-dependency

[Ralf Treinen]

Source: gitaly
Version: 13.4.6+dfsg1-2
Severity: serious
Usertags: edos-uninstallable

Hello,

gitaly build-depends on golang-gopkg-libgit2-git2go.v28, but this
package was removed from sid on 2021-02-08.

-Ralf.