update jackson databind nullable to 0.2.11

[wing328]

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Summary by cubic

Bump org.openapitools:jackson-databind-nullable to 0.2.11 across Java/Kotlin generator templates and samples to keep generated projects on the latest nullable support.

• Dependencies
  • Set jackson-databind-nullable to 0.2.11 in Gradle/Maven/SBT templates for Apache HttpClient, Feign, Google API Client, Jersey 2/3, OkHttp-Gson, Rest Assured, RestClient, Resteasy, RestTemplate, Retrofit2, Vert.x, WebClient, Java JAX-RS (incl. Quarkus), Java Spring (SB3/SB4), Helidon, Kotlin Spring, and related test templates.
  • Updated all affected sample projects to the same version.

^{Written for commit 6ed0d38. Summary will update on new commits.}

[cubic-dev-ai]

No issues found across 319 files

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