[Java] fix deserialization of readonly properties

[borsch]

Fix for #10167 (comment)
Workaround that will skip @JsonDeserialize(as = LinkedHashSet.class) over nullable Set (the one with JsonNullable)

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[wing328]

Thanks for the PR. Can you please PM me via https://join.slack.com/t/openapi-generator/shared_invite/zt-12jxxd7p2-XUeQM~4pzsU9x~eGLQqX2g when you've time?

[wing328]

FYI. Add the path to github workflow via 4c330f4