Alias types not getting referenced inside tuples

[HoldYourWaffle]

Possibly related to #232.

/** @minLength 2 */
type Word = string;
type AliasedTupleType = [Word, Word];

Results in (modified for clarity):

{
    "$schema": "http://json-schema.org/draft-07/schema#",
    "definitions": {
        "AliasedTupleType": {
            "additionalItems": {
				"this should be false": "but it isn't because of #208",
				"the maxItems constraint is also missing": "because of the same issue"
			},
            "items": [
                { "type": "string" },
                { "type": "string" }
            ],
			"minItems": 2,
            "type": "array"
        },
        "Word": {
            "minLength": 2,
            "type": "string"
        }
    }
}

I'd expect the items property of AliasedTupleType to be generated like this:

"items": [
	{ "$ref": "#/definitions/Word" },
	{ "$ref": "#/definitions/Word" }
],

Using --aliasRefs does not make any difference.
I'd love to create a PR for this myself but I have literally no idea where to start with this, so any pointers would be greatly appreciated 😄

This would also fix #283.