Consider support for the QUERY method

[ahl]

See https://httpwg.org/http-extensions/draft-ietf-httpbis-safe-method-w-body.html

It seems that QUERY is very much like GET with a body. While a body param is (I guess) fine for GET, some tooling and services disallow or ignore it. It seems like we'll want to adopt this sooner rather than later. Whether we'll use it in omicron (or other Oxide repos) remains to be seen. There's a bunch of work this would depend upon, including:

• feat: add support for HTTP QUERY method hyperium/http#717
• OpenAPI 3.2 will apparently include the QUERY method
• support in Dropshot for OpenAPI 3.1 (i.e. and later -- 3.2 is a more minor update from 3.1 than 3.1 was from 3.0.x)