feat(spring): enable openApiNullable with useJackson3

[sonallux]

fixes #23324

• Remove the constraint that option openApiNullable is not allowed with useJackson3. PR feature(jackson3) add jackson3 support for spring generator #22854 introduced this constraint, because no Jackson 3 compatible version of jackson-databind-nullable was available
• Update jackson-databind-nullable to version 0.2.10 which supports both Jackson 2 and Jackson 3 (see PR Implement Jackson3 support and maintain Jackson2 support jackson-databind-nullable#117)

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[cubic-dev-ai]

No issues found across 296 files

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[wing328]

thanks for the PR

please review the build failure when you've time

cc @cachescrubber (2022/02) @welshm (2022/02) @MelleD (2022/02) @atextor (2022/02) @manedev79 (2022/02) @javisst (2022/02) @borsch (2022/02) @banlevente (2022/02) @Zomzog (2022/09) @martin-mfg (2023/08)

[sonallux]

@wing328 die failing tests in "Samples JAX-RS" seem unrelated to me. I am also not getting any new changes when running the generate samples script.