Fixed: Unable to close indexer category select input on mobile

Closes #4296

frontend/src/Components/Form/EnhancedSelectInput.css

@@ -85,3 +85,21 @@
   display: inline-block;
   margin: 5px -5px 5px 0;
 }
+
+.mobileCloseButtonContainer {
+  display: flex;
+  justify-content: flex-end;
+  height: 40px;
+  border-bottom: 1px solid $borderColor;
+}
+
+.mobileCloseButton {
+  width: 40px;
+  height: 40px;
+  text-align: center;
+  line-height: 40px;
+
+  &:hover {
+    color: $modalCloseButtonHoverColor;
+  }
+}

frontend/src/Components/Form/EnhancedSelectInput.js

@@ -9,6 +9,7 @@ import * as keyCodes from 'Utilities/Constants/keyCodes';
 import { icons, sizes, scrollDirections } from 'Helpers/Props';
 import Icon from 'Components/Icon';
 import Portal from 'Components/Portal';
+import IconButton from 'Components/Link/IconButton';
 import Link from 'Components/Link/Link';
 import LoadingIndicator from 'Components/Loading/LoadingIndicator';
 import Measure from 'Components/Measure';
@@ -518,6 +519,18 @@ class EnhancedSelectInput extends Component {
                 scrollDirection={scrollDirections.NONE}
               >
                 <Scroller className={styles.optionsModalScroller}>
+                  <div className={styles.mobileCloseButtonContainer}>
+                    <Link
+                      className={styles.mobileCloseButton}
+                      onPress={this.onOptionsModalClose}
+                    >
+                      <Icon
+                        name={icons.CLOSE}
+                        size={18}
+                      />
+                    </Link>
+                  </div>
+
                   {
                     values.map((v, index) => {
                       const hasParent = v.parentKey !== undefined;

frontend/src/Components/Form/EnhancedSelectInputOption.css

@@ -54,4 +54,8 @@
   &:last-child {
     border: none;
   }
+
+  &:hover {
+    background-color: unset;
+  }
 }

frontend/src/Components/Form/EnhancedSelectInputOption.js

@@ -12,7 +12,9 @@ class EnhancedSelectInputOption extends Component {
   //
   // Listeners
 
-  onPress = () => {
+  onPress = (e) => {
+    e.preventDefault();
+
     const {
       id,
       onSelect