Fix konsolepart Segfault when closed

Assign the _view as the parent to the KXMLGuiFactory because the factory
is referencing the view widget as its associated widget. Since the
TerminalDisplay gets destructed first this is now a dangling pointer.
If the view is set as the parent the factory gets cleaned up correctly.

Also cleanup the created clientBuilder after destruction because it
cant have a parent and would probably leak memory.

BUG: 415762
BUG: 421226
BUG: 421194
BUG: 421138