reduces height of filter dropdowns

opentech/static_src/src/sass/apply/components/_select2.scss

+$dropdown-height: 45px;
+
 .select2 {
     &-container {
         z-index: 99995; // to override any modals
@@ -8,7 +10,7 @@
         width: 100% !important; // sass-lint:disable-line no-important
 
         .select2-selection--single {
-            height: 55px;
+            height: $dropdown-height;
             border: 1px solid $color--mid-grey;
             border-radius: 0;
 
@@ -30,12 +32,12 @@
 
             .select2-selection__rendered {
                 padding-left: 15px;
-                line-height: 55px;
+                line-height: $dropdown-height;
             }
 
             .select2-selection__arrow {
                 right: 15px;
-                height: 53px;
+                height: $dropdown-height;
                 pointer-events: none;
                 background: url('./../../images/dropdown.svg') transparent no-repeat 95% center;
                 background-size: 8px;