feat: support date-time-local in scala generators

[plaflamme]

Adds support for the OAS3 date-time-local format and map it to LocalDateTime which is then mapped to either java.time.LocalDateTime or org.joda.time.LocalDateTime accrodingly

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cc @clasnake (2017/07), @shijinkui (2018/01), @ramzimaalej (2018/03), @chameleon82 (2020/03), @Bouillie (2020/04) @Fish86 (2023/06)

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Summary by cubic

Add OAS 3 date-time-local support to Scala generators. Fields with this format now generate as LocalDateTime, importing java.time.LocalDateTime when using the java8 date library.

• New Features
  • Map date-time-local to LocalDateTime in AbstractScalaCodegen.
  • Add import for java.time.LocalDateTime when dateLibrary=java8.
  • Tests: verify type mapping and generated model imports; include new sample spec (date-time-local.yaml).

^{Written for commit 6927e92. Summary will update on new commits.}

[cubic-dev-ai]

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