Generated OpenAPI doesn't include POST requests for Features endpoints

[mikemahoney218-usgs]

Description
The generated OpenAPI document lists GET and OPTIONS requests for Features endpoints, but does not list POST requests. This is particularly important for endpoints from providers which support CQL, though endpoints that don't support CQL also accept POST requests -- for instance:

curl --location --request POST 'https://demo.pygeoapi.io/master/collections/obs/items' --data-raw '{}'

Steps to Reproduce
Generate an OpenAPI document for a Features endpoint. Examples:
https://api.waterdata.usgs.gov/ogcapi/v0/openapi
https://api.weather.gc.ca/openapi?f=html

Expected behavior
I expected POST requests to be documented.

Environment

• pygeoapi version: 0.20.dev0

[github-actions]

This Issue has been inactive for 90 days. As per RFC4, in order to manage maintenance burden, it will be automatically closed in 7 days.

[mikemahoney218-usgs]

This is still relevant https://demo.pygeoapi.io/master/openapi?f=html

[tomkralidis]

Related: opengeospatial/ogcapi-features#771