not yet implemented: expected one content entry, found 4

Thanks for this library! I'm giving it a go for work purposes (https://github.com/brainstorm/ica-rs), unfortunately:

% cargo run
   Compiling ica-rust v0.1.0 (/Users/rvalls/dev/umccr/ica-rust)
error: proc macro panicked
 --> src/main.rs:4:5
  |
4 |     generate_api!(spec = "openapi/gds.json");
  |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  |
  = help: message: not yet implemented: expected one content entry, found 4

The offending .json can be obtained like so:

wget https://converter.swagger.io/api/convert?url=https%3A%2F%2Faps2.platform.illumina.com%2Fgds%2Fswagger%2Fv1%2Fswagger.json -O gds.json

I'll keep digging, I just wanted to make sure whether you or somebody else was planning to support multiple content entries before I deep dive on it ;)

Start by reproducing the failure with cargo run in the reporter's ica-rust example and the openapi/gds.json document, then trace the generate_api! proc-macro handling of response content entries. Done means the generator accepts this document with four content entries and the example builds successfully.