Prequalify a pull request for adding audio content to hotspots

[ColinBD]

I want to prequalify a pull request to make audio content available through image hotspots.
Currently, image hotspots 1.8.3 only offers choices for hotspot content of text, video, and image. However, it would be useful to have the option of playing audio files when hotspots are clicked.

I am working on a project related to language learning and so I want to create an image of items, place a hotspot upon each depicted item and then allow the user to hear the pronunciation for the item’s associated word when the hotspot is clicked.

A search on H5P.org reveals that others have previously asked for audio to be made available as a hotspot option. For example: https://h5p.org/node/252524, https://h5p.org/node/85262, https://h5p.org/node/45583

Technical solution:
I have added the audio player library (H5P.Audio 1.4) as an option to the image hotspots library’s semantics.json file. The list is therefore now H5P.Text, H5P.Video, H5P.Image, and H5P.Audio.

UX:
The audio library offers good UX options so authors should have no problems configuring the hotspot audio to suit their needs.

Accessibility:
Not relevant

P.S. This is my first ever pull request and first attempt at contributing to the work of the open source community!