use align-items on .form-inline to keep items from growing too much (#21461)

scss/_forms.scss

@@ -298,6 +298,7 @@ select.form-control-lg {
 .form-inline {
   display: flex;
   flex-flow: row wrap;
+  align-items: center; // Prevent shorter elements from growing to same height as others (e.g., small buttons growing to normal sized button height)
 
   // Because we use flex, the initial sizing of checkboxes is collapsed and
   // doesn't occupy the full-width (which is what we want for xs grid tier),