Changed aria-level attribute to correct syntax. (#2032)

* Changed aria-level attribute to correct syntax.

Changed the aria-level attribute to the correct syntax. Changes were also made to meet ADA compliance.

* update a few more aria-level attributes

Co-authored-by: Renée Kooi <renee@kooi.me>

packages/@uppy/dashboard/src/components/AddFilesPanel.js

@@ -9,7 +9,7 @@ const AddFilesPanel = (props) => {
       aria-hidden={props.showAddFilesPanel}
     >
       <div class="uppy-DashboardContent-bar">
-        <div class="uppy-DashboardContent-title" role="heading" aria-level="h1">
+        <div class="uppy-DashboardContent-title" role="heading" aria-level="1">
           {props.i18n('addingMoreFiles')}
         </div>
         <button

packages/@uppy/dashboard/src/components/FileCard/index.js

@@ -85,7 +85,7 @@ class FileCard extends Component {
         onPaste={ignoreEvent}
       >
         <div class="uppy-DashboardContent-bar">
-          <div class="uppy-DashboardContent-title" role="heading" aria-level="h1">
+          <div class="uppy-DashboardContent-title" role="heading" aria-level="1">
             {this.props.i18nArray('editing', {
               file: <span class="uppy-DashboardContent-titleFile">{file.meta ? file.meta.name : file.name}</span>
             })}

packages/@uppy/dashboard/src/components/PickerPanelContent.js

@@ -14,7 +14,7 @@ function PickerPanelContent (props) {
       onPaste={ignoreEvent}
     >
       <div class="uppy-DashboardContent-bar">
-        <div class="uppy-DashboardContent-title" role="heading" aria-level="h1">
+        <div class="uppy-DashboardContent-title" role="heading" aria-level="1">
           {props.i18n('importFrom', { name: props.activePickerPanel.name })}
         </div>
         <button

packages/@uppy/dashboard/src/components/PickerPanelTopBar.js

@@ -90,7 +90,7 @@ function PanelTopBar (props) {
         <div />
       )}
 
-      <div class="uppy-DashboardContent-title" role="heading" aria-level="h1">
+      <div class="uppy-DashboardContent-title" role="heading" aria-level="1">
         <UploadStatus {...props} />
       </div>