[Feature] HTML format

[fmigneault]

To allow search engine crawlers to find processes, HTML format could be provided.
(embedded XML equivalent of the JSON body?)

https://github.com/opengeospatial/ogcapi-processes/blob/e16190bd990baf0933bbb42626fe8a719bc2c2c2/core/recommendations/core/REC_html.adoc

Response should be supported using either Accept header or f/format query parameter
(relates to #125)

Using a Link on HTML view of the process description, there could be a redirect to a page for submitting jobs with HTML form.

For job submission, consider using utilities like:

• https://dash.plotly.com/dash-core-components (I/O types)
• https://dash.plotly.com/dash-html-components (I/O types)
• https://dash.plotly.com/dash-core-components/upload (File)
• https://dash.plotly.com/integrating-dash (webapp)
• https://dash.plotly.com/advanced-callbacks (error handling)
• https://dash.plotly.com/long-callbacks (run job)

And for reporting/getting the job status:

• https://dash.plotly.com/dash-core-components/link
• https://dash.plotly.com/dash-core-components/loading
• https://dash.plotly.com/dash-html-components/progress

Other alternatives to consider:

• https://panel.holoviz.org/user_guide/FastAPI.html
• https://docs.pylonsproject.org/projects/pyramid_layout/en/latest/index.html (?)

Relates to GD-533