[hutiefang76]

Why are the changes needed?

The OpenAPI SDK is the agreed SDK-only slice of the JUnit migration in #4203. Its health-check test still uses JUnit 4 annotations and Java assert statements.

Closes #4459. Closes part of #4203.

Brief change log

• Migrate OpenAPITest to Jupiter lifecycle/test annotations and always-active Jupiter assertions, preserving all four response checks and WireMock's dynamic port and cleanup.
• Remove the SDK's redundant direct JUnit 4 dependency. The parent JUnit 4/Vintage setup and shared test bases remain unchanged for the other migration steps.

How was this patch tested?

• Run test locally before making a pull request.

JDK 17, before and after the migration:

./mvnw -B clean package -pl amoro-openapi-sdk -am -Popenapi-sdk

Both runs executed OpenAPITest: 1 test, 0 failures, 0 errors, 0 skipped. The build also passed the SDK's Spotless and Checkstyle checks.

./mvnw -B validate

All 33 modules in the default reactor passed. The SDK is enabled separately by -Popenapi-sdk and is covered by the first command. Upstream CI passed at 1b9d1c07: the OpenAPI SDK build ran OpenAPITest (1 test, 0 failures, 0 errors, 0 skipped); the JDK 11 dependency build succeeded with tests skipped, and the PR labeler passed.

Documentation

No new feature; documentation is not applicable.

_{Implementation and this description were prepared with AI assistance.}