Bug 31132: (follow-up) Reset dropdown values and style button

Bug 31132: (follow-up) Reset dropdown values and style button

This follow-up patch resets the dropdown values of the form alongside
the text inputs. It styles the button to look like a link so it doesn't
distract the user and get 'accidentally' clicked when attempting to
submit.

Test that the button looks and behaves as expected after submitting a
search.

Signed-off-by: nicolas <nicolas@inlibro.com>
Signed-off-by: Katrin Fischer <katrin.fischer.83@web.de>
Signed-off-by: Tomas Cohen Arazi <tomascohen@theke.io>