[php-nextgen] Check for $openApiType === "string" instead of "\DateTime" in ObjectSerializer

[wbohlken]

ObjectSerializer incorretly validates the $openApiType equals \DateTime. This is not a valid OpenAPI type, instead, it should validate the type to be string.

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[cubic-dev-ai]

No issues found across 1 file

_{Re-trigger cubic}

[wbohlken]

@jebentier @dkarlovi @mandrean @jfastnacht @ybelenko @renepardon

[wing328]

lgtm. let's give it a try

thanks for the contribution.

[wing328]

By the way your commit (as shown in the Commits tab) is not linked to your Github account, which means this PR won't count as your contribution in https://github.com/OpenAPITools/openapi-generator/graphs/contributors.

Let me know if you need help fixing it.

Ref: https://github.com/OpenAPITools/openapi-generator/wiki/FAQ#how-can-i-update-commits-that-are-not-linked-to-my-github-account