tests/uri-parsing: check empty username/password
tests/uri-parsing: check empty username/password

Make sure that zero-length username/password are recognized as
different from no username/password.

jwendell/libsoup,jwendell/libsoup,Distrotech/libsoup,Distrotech/libsoup,Distrotech/libsoup,jwendell/libsoup,fanc999/libsoup,fanc999/libsoup,Distrotech/libsoup,fanc999/libsoup,jwendell/libsoup,Distrotech/libsoup,fanc999/libsoup,fanc999/libsoup,jwendell/libsoup