userportal: add 3 exclude to findbugs filter.

Similar to webadmin, the *Presenter classes have a redundant
warning on selectedItems field. It should be ignored by findbugs.

Change-Id: I7c2c7846358d135c9c19fb4cde585f47e50f5ad2
Signed-off-by: Alissa Bonas <abonas@redhat.com>