Orator play button may accidentally submit form

When in the Story Edit page on the Storytelling Tool staging site, if I select a piece of text, the Orator will appear and offer to play it using the selectionReader. If that piece of text happens to be within the <form> element of the editor (i.e. the block editing or metadata areas), then clicking "Play" submits the form and reloads the page.

To reproduce:

1. Go to the Storytelling Tool staging site's Edit page: https://staging-stories.floeproject.org/storyEdit.html
2. Select a piece of text within the "Story Builder" area in the middle of the page (see screenshots for examples)
3. Click "Play" on the selectionReader

Expected:

The text is voiced by the Orator

Actual:

The form is submitted

Proposed fix:

The Play button should be updated to make it a "button" type button. I.e. on this line of the component configuration that defines the markup for the selectionReader, the "type" attribute should be specified (see "2020-06-02 orator bug fix.png" for an example). This is because if the "type" attribute is missing, the default behaviour is to submit the form.