Add accessible name label for Progress component

Fixes the error: One of aria-label or aria-labelledby properties should
be passed when using the progress component without a title.

src/player.jsx

@@ -1273,6 +1273,7 @@ export class Player extends React.Component {
                 label={timeStr}
                 value={this.state.curTS}
                 onClick={this.handleProgressClick}
+                aria-label="Player Progress"
             />
         );