[modosc]

adds openapi 3.1 support, using openapi_parser 2.4.

• routes 3.1 docs to the openapi 3 driver (the openapi version is parsed once as a Gem::Version, so 3.1 and unquoted yaml 3.1 work too)
• adds Committee::Utils.schema_type to handle array-form type (e.g. [array, "null"]) in param deserialization and test dummy values
• bumps the openapi_parser dependency to ~> 2.4
• readme section on what 3.1 features are and aren't supported

like openapi_parser, the runtime doesn't check the declared version, so array-form type also works in 3.0 docs (previously array/object params with it failed). strict_specification_version: :warn flags it.

tests cover:

• query/path coercion, constraints after coercion
• const
• numeric exclusive bounds
• prefixItems
• components.pathItems
• webhooks not being routed
• response validation
• array-form type in every deserializer style, the except test helpers, and 3.0 docs

not yet supported:

• $dynamicRef / $dynamicAnchor
• if / then / else
• unevaluatedProperties
• dependentRequired
• patternProperties
• $ref siblings

closes #352

[geemus]

lgtm, thanks!