fix: remove unnecessary @NotNull annotation from path variable

[jorgerod]

Closes #23093

PR #21951 added @NotNull to all @PathVariable parameters in the Spring generator. This is both a breaking change that should not have landed in a minor release, and it is technically unnecessary.

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cc/ @GregDThomas @wing328 @kolomanschaft

---

Summary by cubic

Removed unnecessary @NotNull from generated Spring @PathVariable parameters to prevent a breaking change and match Spring’s behavior that path variables are already required. Fixes #23093.

• Bug Fixes
  • Updated JavaSpring/beanValidationPathParams.mustache to drop @NotNull while preserving other bean validations.
  • Regenerated samples to remove @NotNull from path variables across Spring client and server templates.

^{Written for commit b946d44. Summary will update on new commits.}

[cubic-dev-ai]

No issues found across 159 files

Note: This PR contains a large number of files. cubic only reviews up to 75 files per PR, so some files may not have been reviewed.

[MelleD]

@jorgerod nice you are completely right. Maybe you can give also your two cents here, because here are is somebody the complete different opinion.

#22291

[MelleD]

@wing328 for me thats the right way so approved

[wing328]

closed via #23096 instead