[JENKINS-47020] - Improve job search experience (#3324)

* Increase search results limit from 20 to 100

Signed-off-by: Sorin Sbarnea <ssbarnea@redhat.com>

* Enlarge search box size

Increase the max number of results from 10 to 25.
Increase width of results from 25em to 35em
in order to suit longer job names.

This still fits even small 13" screens and improves
user experience.

Signed-off-by: Sorin Sbarnea <ssbarnea@redhat.com>