Bug 14909: Warnings from search_utf8.t when empty idx= misses in base

Bug 14909: Warnings from search_utf8.t when empty idx= misses in base

The regex in this test looks like:
  opac-search.pl\?idx=&q=%CE%91%CE%B8%CE%AE%CE%BD%CE%B1
The result it got was:
  opac-search.pl?q=%CE%91%CE%B8%CE%AE%CE%BD%CE%B1

The empty idx should not be a reason to fail the test. I changed the
original regex to make the 'idx=&' part optional and added a base_unlike
test to verify that the base does not include a idx=\w+ anywhere.

Also corrected the typo Goog. Good!

Signed-off-by: Marcel de Rooy <m.de.rooy@rijksmuseum.nl>
All 66 tests now pass with me.

Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>
Signed-off-by: Tomas Cohen Arazi <tomascohen@unc.edu.ar>