MDL-69703 theme_boost: remove right padding for multi-selects.

This removes the whitespace obscuring longer option elements when
selected, particularly on narrow screens.

theme/boost/scss/moodle/forms.scss

@@ -338,6 +338,13 @@ fieldset.coursesearchbox label {
     font-size: large;
 }
 
+select.form-control {
+    &[size],
+    &[multiple] {
+        padding-right: 0;
+    }
+}
+
 /* Non-bootstrap selects with a size show their contents outside of the element.
  * Remove when we update to stable bootstrap 4. (MDL-56511) */
 select[size],

theme/boost/style/moodle.css

@@ -16616,6 +16616,9 @@ fieldset.coursesearchbox label {
   padding: 0.5em;
   font-size: large; }
 
+select.form-control[size], select.form-control[multiple] {
+  padding-right: 0; }
+
 /* Non-bootstrap selects with a size show their contents outside of the element.
  * Remove when we update to stable bootstrap 4. (MDL-56511) */
 select[size],

theme/classic/style/moodle.css

@@ -16842,6 +16842,9 @@ fieldset.coursesearchbox label {
   padding: 0.5em;
   font-size: large; }
 
+select.form-control[size], select.form-control[multiple] {
+  padding-right: 0; }
+
 /* Non-bootstrap selects with a size show their contents outside of the element.
  * Remove when we update to stable bootstrap 4. (MDL-56511) */
 select[size],