fixes(spring) Fixes @Nullable annotation

[antechrestos]

• remove findbug dependency as spring generator set its import to org.springframework.lang.Nullable
• for springboot 4, use org.jspecify.annotations.Nullable as spring one is Deprecated(see java doc)

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Summary by cubic

Fixes @nullable handling in Spring generators: use org.jspecify.annotations.Nullable for Spring Boot 4 and org.springframework.lang.Nullable otherwise. Removes jsr305 from generated POMs to avoid deprecated annotations and keep builds clean.

• Bug Fixes

  • Import Nullable based on Spring Boot version (SB4 -> org.jspecify.annotations.Nullable, else org.springframework.lang.Nullable).
  • Added tests to ensure correct imports for array-type models under Spring Boot 4.

• Dependencies

  • Removed com.google.code.findbugs:jsr305 from Spring Boot, Spring Cloud, and HTTP Interface templates; updated samples to match.

^{Written for commit b2b3076. Summary will update on new commits.}

[cubic-dev-ai]

No issues found across 135 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.

[antechrestos]

@cachescrubber @wing328 I need you memory on this subject.

I would like to use @Nullable annotation from jspecify instead of springboot (the spring boot one is deprecated in springboot 7), yet there is a potential issue.

As jspecify Nullable annotation is a TYPE_USE annotation, it should be written org.springframework.core.io.@Nullable Resource instead of @Nullable org.springframework.core.io.Resource.

I though that a good workaround could be to add an importMapping of org.springframework.core.io.Resource and just use the type Resource in fields, getters and setters.

Yet I looked at the history and ended on your modification @cachescrubber .

As I do not understand very well reason why this revert, and, whether it is needed todays, I am asking your help to understand that before pushing a bug.

Thank you by advance

[jpfinne]

@antechrestos @wing328 org.springframework.core.io.Resource is just one example of Fully Qualified Class Name.
It can also occur with SchemaMappings as described in #23206

#23256 fixes it ([java] [Spring] useJspecify for java clients and spring generator). It works except for an issue with github workflows. An access Denied that I don't know how to fix. Please help on that.
Removing findbugs can be a minor improvement.

[antechrestos]

@jpfinne I think I found your right issue on your PR. Please take a look at my comment