Rename button label of the Save and Download action save dialog (#2727)

The label was `Send and Save`, it is confusing because actually the request was already sent.

packages/insomnia-app/app/ui/containers/app.js

@@ -621,7 +621,7 @@ class App extends PureComponent {
   async _getDownloadLocation() {
     const options = {
       title: 'Select Download Location',
-      buttonLabel: 'Send and Save',
+      buttonLabel: 'Save',
     };
 
     const defaultPath = window.localStorage.getItem('insomnia.sendAndDownloadLocation');