Display the play/pause button on the Slideshow even when Autoplay is disabled

On the Slideshow block if the `Autoplay` toggle is disabled the play/pause button at the top right of the slideshow is removed entirely.

Even if the `Autoplay` is disabled, it would nice if the play/pause button is still shown but in the Paused state, so site visitors can still click and play the slideshow if they prefer.

User report: 27171989-hc

Start at the Slideshow block and trace how the Autoplay toggle controls the play/pause button in the top-right. Verify the disabled-Autoplay state in the editor or a local WordPress site, then make sure the control remains visible in a paused state and can start the slideshow when clicked.

Written by the indexing model from the issue text.