Stage dropdown lists style corrections
Summary
When reviewing a merge request, in the dropdown list of a stage, the list elements are misaligned. This may cause confusion when clicking the action buttons and when there are too many elements in the list too.
![Screen_Shot_2019-12-11_at_4.53.37_PM](data:image/gif;base64,R0lGODlhAQABAAAAACH5BAEKAAEALAAAAAABAAEAAAICTAEAOw==)