Remove inline padding from <gl-search-box-by-type>

Inline padding to the search box was added in this MR !18772 (merged) to make it go from this: Screen_Shot_2019-10-18_at_5.27.50_PM

to this: Screen_Shot_2019-10-22_at_6.59.39_PM

There's an MR in place to fix the search box: gitlab-ui!852 (closed) (currently blocked)

Once that MR is completed, then this MR can be completed.