ui: reset margin between list of databases and category header
ui: reset margin between list of databases and category header

Otherwise the list of databases and the corresponding category header
(nucleotide, protein) were rendered so far apart on some browsers that it
looked odd.

Signed-off-by: Anurag Priyam <6e6ab5ea9cb59fe7c35d2a1fc74443577eb60635@gmail.com>

aldermossy/sequenceserver,deepakunni3/sequenceserver,aldermossy/sequenceserver,lepbase/lepbase-sequenceserver,deepakunni3/sequenceserver,yeban/sequenceserver,lepbase/lepbase-sequenceserver,aldermossy/sequenceserver,jasminZ/sequenceserver,jasminZ/sequenceserver,yeban/sequenceserver,elsiklab/sequenceserver,yeban/sequenceserver,aldermossy/sequenceserver,elsiklab/sequenceserver,deepakunni3/sequenceserver,jasminZ/sequenceserver,IsmailM/sequenceserver,vivekiitkgp/sequenceserver,lepbase/lepbase-sequenceserver,elsiklab/sequenceserver,IsmailM/sequenceserver,IsmailM/sequenceserver,vivekiitkgp/sequenceserver,vivekiitkgp/sequenceserver,yeban/sequenceserver