Bug#1051340: libmono-cil-dev: Drop unnecessary Depends on libnunit-cil-dev

[Bastian Germann]

Source: libmono-cil-dev
Version: 5.18.0.240+dfsg-3
Severity: important

libmono-cil-dev depends on libnunit-cil-dev without a good reason,
which makes nunit and subsequently nuget key packages.
Please drop this Depends, so nuget can be autoremoved.