refactor: introduce function for getting Schema Object type

[char0n]

use function for getting schema object type/schema object type label depending on the OpenAPI version

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Attribution: @robert-hebel-sb

[char0n]

To be consistent with JSON Schema 2020-12 processing, can we make the fallback type the string type?

Suggested change

	export const getSchemaObjectType = (schema) => schema.type ?? "any"
	export const getSchemaObjectType = (schema) => schema.type ?? "string"

Also, may I suggest to make this function safe:

Suggested change

	export const getSchemaObjectType = (schema) => schema.type ?? "any"
	export const getSchemaObjectType = (schema) => schema?.type ?? "string"

[char0n]

Preferred alternative: What if both the functions would have the following signature?

getSchemaObjectType: (schema: object) -> string
getSchemaObjectTypeLabel: (schema: object) -> string

This would simplify their usage inside the code as it is now abstracted how the the type or label are computed from the schema.

Instead of

const typeLabel = fn.getSchemaObjectTypeLabel(immutableToJS(schema?.get("type")))

you'll end up having

const typeLabel = fn.getSchemaObjectTypeLabel(immutableToJS(schema))

If you further abstract and allow the functions to consume immutable along with POJO, it can look like:

const typeLabel = fn.getSchemaObjectTypeLabel(schema)

NOTE: this applies both for Draft 5 and 2020-12 functions.

[char0n]

The input is type not a label.

Suggested change

	export const getSchemaObjectTypeLabel = (label) => label
	export const getSchemaObjectTypeLabel = (type) => type

But anyway we can make this point-free by:

import identity from "lodash/identity"

export const getSchemaObjectTypeLabel = identity

[char0n]

This looks a bit confusing. For getting a typeLabel we're using getSchemaObjectType. For actual type we're using getSchemaObjectTypeLabel. Shouldn't it be reversed?