[BUG][typescript-rxjs] Nested oneOf in allOf not generated - but can be correctly generated if nested inside oneOf

Bug Report Checklist

• Have you provided a full/minimal spec to reproduce the issue?
• Have you validated the input using an OpenAPI validator (example)?
• Have you tested with the latest master to confirm the issue still exists?
• Have you searched for related issues/PRs?
• What's the actual output vs expected output?
• [Optional] Sponsorship to speed up the bug fix or feature request (example)

Description

Generating TS type when the yaml defines a "oneOf" nested inside an "allOf" does not generate the correct type. Generation misses out the oneOf completely.

Strangely, if you nest the whole object inside a "oneOf" the generator will then generate the nested oneOf type correctly. See below for examples.

openapi-generator version

6.6.0 (latest)

OpenAPI declaration file content or url

See failing spec here, oneOf nested inside allOf:
https://gist.github.com/LeoCie/1985bee1f2d69cb56734f25c4486bc86

Produces TS type:

import type {
    CommonBlock,
} from './';

export type OrdinaryDetailBlock = CommonBlock;

though I would expect:

import type {
    CommonBlock, OrdinaryDetailBlockOneOf 
} from './';
export type OrdinaryDetailBlock = CommonBlock & OrdinaryDetailBlockOneOf ;

and

import type {
    BlockA, BlockB
} from './';
export type OrdinaryDetailBlockOneOf = BlockA | BlockB

See spec here where I nest the whole type inside a oneOf:
https://gist.github.com/LeoCie/3bc37916208219cc537d5d2f96fc12e0

Produces correct TS types:

export type OrdinaryDetailBlock = OrdinaryDetailBlockOneOf

export type OrdinaryDetailBlockOneOf = CommonBlock & OrdinaryDetailBlockOneOfAllOf;

export type OrdinaryDetailBlockOneOfAllOf = BlockA | BlockB;

Generation Details

Generating typescript-rxjs types.

Steps to reproduce

Download gist above, run generator with typescript-rxjs.

Suggest a fix

Start with the two linked gist specifications and run the typescript-rxjs generator as described to compare nested oneOf handling under allOf. Trace the generator path that produces OrdinaryDetailBlock and add a regression test; done means the generated types include the expected intersection and union types for both cases.