Remove upper boundary version-constraints of dependent packages

[fgheysels]

Arcus.Messaging uses lower and upper-bound version constraints on certain packages.
Specifying upper bound version constraints bites us in the back when using Arcus in real projects. It's better to just remove those upper bound version constraints.

[stijnmoreels]

For library development that is not the case, as we saw this in the past and upper versions helps us to showcase what we support instead of supporting every upper version and people having obscure runtime failures instead.