Fixes React.js console errors (#7829)

res/css/views/elements/_GenericEventListSummary.scss

@@ -18,6 +18,11 @@ limitations under the License.
     position: relative;
 }
 
+.mx_GenericEventListSummary_unstyledList {
+    list-style: none;
+    padding: 0;
+}
+
 .mx_TextualEvent.mx_GenericEventListSummary_summary {
     font-size: $font-14px;
     display: inline-flex;

src/components/views/elements/GenericEventListSummary.tsx

@@ -70,7 +70,9 @@ const GenericEventListSummary: React.FC<IProps> = ({
     if (events.length < threshold) {
         return (
             <li className="mx_GenericEventListSummary" data-scroll-tokens={eventIds} data-expanded={true} data-layout={layout}>
-                { children }
+                <ol className="mx_GenericEventListSummary_unstyledList">
+                    { children }
+                </ol>
             </li>
         );
     }

src/components/views/rooms/EventTile.tsx

@@ -1362,6 +1362,7 @@ export default class EventTile extends React.Component<IProps, IState> {
             reactionsRow = <ReactionsRow
                 mxEvent={this.props.mxEvent}
                 reactions={this.state.reactions}
+                key="mx_EventTile_reactionsRow"
             />;
         }