Relayouting event of plotly.js is not documented

[dmt0]

• Relayouting event is not described on this page: https://plotly.com/javascript/plotlyjs-events/
• It is also worth checking if there are other plotly.js events that are not documented.
• This page, it has a lot of links to itself without hashes - for example all links in second paragraph of this section: https://plotly.com/javascript/plotlyjs-events/#event-data
• plotly_sunburstclick - discovered by a contributor here: Add support for onSunburstClick/plotly_sunburstclick event react-plotly.js#203
• plotly_beforehover - discovered by a contributor here: add plotly_beforehover event react-plotly.js#216 also relevant: plotly_beforehover event doesn't work on 3d plots plotly.js#5309