comment and remove unnecessary lines of code

src/client/js/components/Admin/Import/GrowiZipImportForm.jsx

@@ -101,6 +101,7 @@ class GrowiImportForm extends React.Component {
                         <tr>
                           <td className="text-muted" colSpan="3">
                             TBD: define how to import {collectionName}
+                            {/* TODO: create a component for each collection to modify this.state.schema */}
                           </td>
                         </tr>
                       )}

src/client/js/components/Admin/Import/GrowiZipImportSection.jsx

@@ -13,14 +13,11 @@ class GrowiZipImportSection extends React.Component {
   constructor(props) {
     super(props);
 
-    this.initialState = {
-      meta: {},
+    this.state = {
       fileName: '',
       fileStats: [],
     };
 
-    this.state = this.initialState;
-
     this.inputRef = React.createRef();
 
     this.handleUpload = this.handleUpload.bind(this);