`add_resource()` includes schema verbosely when only url to schema is required

[sannegovaert]

add_resource() is used for the development of write_camtrapdp().

The resources are added with add_resource(schema = path), whereas for schema a path is provided, e.g. "https://raw.githubusercontent.com/tdwg/camtrap-dp/1.0.1/observations-table-schema.json".
add_resource() adds the schema verbosely, while we just want to keep the url.

[peterdesmet]

@sannegovaert wanna take a stab at this? I think it can be done by adding:

schema_url <- if (is_url(schema)) schema else NULL

To:

frictionless-r/R/add_resource.R

Lines 150 to 152 in 8614cf5

	} else if (is.character(schema)) {
	# Path to schema can be unsafe, since schema will be verbosely included
	schema <- read_descriptor(schema, safe = FALSE)

And then using schema_url %||% schema when assigning in:

frictionless-r/R/add_resource.R

Line 192 in 8614cf5

schema = schema

frictionless-r/R/add_resource.R

Line 204 in 8614cf5

schema = schema

And testing for it.

[peterdesmet]

I addition, I think get_schema() should provide an option to get the character rather than the list. E.g.

get_schema(x, "deployments", verbatim = FALSE)