Support machine-readable output for conformance test reports

[AnupamGhosh]

Currently, the MCS API conformance testing tool generates an HTML report. HTML is good for human readability but having a machine readable output like a YAML or JSON makes it easy it easy to create the comparison matrix among all the implementations.

Ginkgo (the framework used in the conformance tests) can produce a JSON report, perhaps that can be used directly here.

[AnupamGhosh]

If JSON is supported then should the tool output both html and json or should it output the report based on a flag passed to the tool? If a flag is introduced in the tool by default in which format should it generate html or json?

[MrFreezeex]

I believe @skitt was talking about this: https://onsi.github.io/ginkgo/#generating-machine-readable-reports which is the default report mechanism of ginkgo while the report html output is a custom one implemented within the conformance code itself.

If we support a custom JSON output / the ginkgo one is not sufficient we probably need some flags to configure that indeed if it's the default one, maybe we don't necessarily need any modification to the conformance code (I don't know what's the output look like though 😅)

[AnupamGhosh]

I looked at report.go — the existing struct data used for the HTML template can be directly encoded and written to a report.json or report.yaml file with minimal changes. JSON uses the standard library (encoding/json), YAML requires gopkg.in/yaml.v3