cmd/snap-update-ns: move Assumption to {System,User}ProfileUpdate
The common implementation has been removed, replacing it with the
two existing implementations, now graduated to proper methods, with
tests and basic documentation.
The new logic is immediately used.
Signed-off-by: Zygmunt Krynicki <email address hidden>
The error was a bit confusing because it was explaining why snap-confine
ignored the absence of cookies. Their absence is still a problem for
other parts of the stack but it was established why snap-confine is not
enforcing their presence.
Signed-off-by: Zygmunt Krynicki <email address hidden>