Tests: do not access invalidated objects
Tests: do not access invalidated objects

Calling the SIGNON_IS_<class>() macros on disposed objects will likely
lead to invalid reads (it does, in the lastest glib) and anyway isn't a
nice way to check if an object has been disposed. Using a weak pointer
is much cleaner and reliable.

plotters/accounts-sso.libsignon-glib,plotters/accounts-sso.libsignon-glib,plotters/accounts-sso.libsignon-glib