Add a page cataloging a curated list of example OpenAPI documents

[SensibleWood]

This issue details a thread in Slack, namely: https://open-api.slack.com/archives/C0KM0KXU6/p1710321260049639

The Petstore API has long been used as the canonical example of an OpenAPI description, partly for reasons of history but also because alternatives comes from different sources that are not always readily apparent and not cataloged in a well-known location. There are many useful alternatives to Petstore - include the Tic Tac Toe example in this repository - that would provide different views of "what good looks like" in API design for the community.

A new page in this repository is therefore proposed to address this:

• The page will provide a curated list of OpenAPI descriptions provided by the community.
• Each will be listed with a brief explanation of the qualities it displays.
• Each will be cataloged against a given version of OpenAPI (with cognizance of the fact the "same" description could appear multiple times, with each instance being at a given version).

The result should be a well-tended and useful list of OpenAPI descriptions that provides the community with multiple references to model APIs.

For the avoidance of doubt: These examples are provided as generic API descriptions that are used for educational purposes. They ARE NOT intended to be pointers to commercial APIs. Whilst OpenAPI members and vendors are encouraged to contribute to this list their submissions are not expected to point to their own APIs. There is a bunch of other stuff on the internet that can serve the purpose of providing references to commercial propositions.

[lornajane]

I'd like to contribute the Museum API to the list. It was created specifically for learning purposes, and while I expect us to add some more features and update it, I believe it is useful in its current form. It's here: https://github.com/Redocly/museum-openapi-example/blob/main/openapi.yaml

[philsturgeon]

• Train Travel API - https://github.com/bump-sh-examples/train-travel-api

• Bike Shop API - https://docs.alphadoc.io/apis/bikeshop%20-%20demo