Fix small style issue

app/assets/stylesheets/framework/dropdowns.scss

@@ -117,7 +117,7 @@
     padding-left: 10px;
     padding-right: 10px;
     color: $dropdown-link-color;
-    line-height: 34px;
+    line-height: 16px;
     text-overflow: ellipsis;
     border-radius: 2px;
     white-space: nowrap;
@@ -167,13 +167,13 @@
 }
 
 .dropdown-menu-user-link {
-  padding-top: 7px;
+  padding-top: 10px;
   padding-bottom: 7px;
 }
 
 .dropdown-menu-user-full-name {
   display: block;
-  font-weight: 600;
+  font-weight: 500;
   line-height: 16px;
   text-overflow: ellipsis;
   overflow: hidden;

app/views/shared/issuable/_sidebar.html.haml

@@ -47,7 +47,7 @@
 
         .selectbox.hide-collapsed
           = f.hidden_field 'assignee_id', value: issuable.assignee_id, id: 'issue_assignee_id'
-          = dropdown_tag('Select assignee', options: { toggle_class: 'js-user-search js-author-search', title: 'Assign user', filter: true, dropdown_class: 'dropdown-menu-user dropdown-menu-selectable dropdown-menu-author', placeholder: 'Search users', data: { first_user: (current_user.username if current_user), current_user: true, project_id: (@project.id if @project), field_name: "#{issuable.to_ability_name}[assignee_id]", issue_update: issuable_json_path(issuable), ability_name: issuable.to_ability_name, null_user: true } })
+          = dropdown_tag('Select assignee', options: { toggle_class: 'js-user-search js-author-search', title: 'Assign to', filter: true, dropdown_class: 'dropdown-menu-user dropdown-menu-selectable dropdown-menu-author', placeholder: 'Search users', data: { first_user: (current_user.username if current_user), current_user: true, project_id: (@project.id if @project), field_name: "#{issuable.to_ability_name}[assignee_id]", issue_update: issuable_json_path(issuable), ability_name: issuable.to_ability_name, null_user: true } })
 
       .block.milestone
         .sidebar-collapsed-icon