Merge branch '2714-margins' into 'master'

Remove left margin for stages with downstream and only one job

Closes #2714

See merge request !2221

app/assets/stylesheets/pages/pipelines.scss

@@ -1183,7 +1183,6 @@
 
   &.has-only-one-job:not(:first-child) {
     margin-right: 36px;
-    margin-left: 0;
 
     .left-connector {
       @include flat-connector-before;
@@ -1234,4 +1233,3 @@
     }
   }
 }
-