feat: style dropdown arrow of html and list select.

client/src/components/SelectList.js

@@ -3,12 +3,11 @@ import {Button} from '@blueprintjs/core';
 import {Select} from '@blueprintjs/select';
 
 export default function SelectList(props) {
-  const {buttonLabel, ...rest} = props;
+  const { buttonLabel, ...rest } = props;
 
   return (
     <Select {...rest}>
       <Button
-        rightIcon="caret-down"
         fill={true}>
           { buttonLabel }
       </Button>