[BUG][Swift5] support of type Array in oneOf

[c-villain]

Tried on master (currently 5.2.0), confirmed that array in "one of" not supported..
Add code-generation support for array type in OneOf..
e.g.

Expected in generated code:

....
case typeArray([MyArray])`
....

for *.YAML - file:

....
oneOf:
     -
        type: array
        items:
            $ref: 'MyArray'
....

Currently code not generated with this spec

[4brunu]

@c-villain do you want to try to create a PR to fix this?

[c-villain]

@4brunu ok, I'll try =)

[mrakko]

@c-villain, @4brunu is there any update in connection with this issue?