Refactor MenuControls as a functional component

* Fix lint errors

awx/ui_next/src/screens/Job/JobOutput/JobOutput.jsx

@@ -164,7 +164,7 @@ class JobOutput extends Component {
 
   loadMoreRows({ startIndex, stopIndex }) {
     if (startIndex === 0 && stopIndex === 0) {
-      return;
+      return Promise.resolve(null);
     }
     const { job } = this.props;
 

awx/ui_next/src/screens/Job/JobOutput/shared/MenuControls.jsx

@@ -1,4 +1,4 @@
-import React, { Component } from 'react';
+import React from 'react';
 import { Button as PFButton } from '@patternfly/react-core';
 import {
   PlusIcon,
@@ -22,19 +22,12 @@ const Button = styled(PFButton)`
   }
 `;
 
-class MenuControls extends Component {
+const MenuControls = ({
-  constructor(props) {
-    super(props);
-  }
-
-  render() {
-    const {
   onScrollTop,
   onScrollBottom,
   onScrollNext,
   onScrollPrevious,
-    } = this.props;
+}) => (
-    return (
   <Wrapper>
     <Button variant="plain">
       <PlusIcon />
@@ -52,8 +45,6 @@ class MenuControls extends Component {
       <AngleDoubleDownIcon />
     </Button>
   </Wrapper>
-    );
+);
-  }
-}
 
 export default MenuControls;