[BUG] - multiple order dependent flaky tests in `swagger/swagger-generator/generator-core`

[pem70]

Steps to Reproduce

Several tests in the swagger/swagger-generator/generator-core module exhibit order-dependent (OD) flakiness. These tests rely on shared state through SwaggerOperations.generate(...) and previously used static fields inside the test classes. These tests previously used a static SwaggerOperations field that was shared across all test methods in the class, and when test methods are executed in different orders, some permutations caused a later test to run after the shared swaggerOperations field had already been cleared.

To reproduce:

mvn edu.illinois.cs:idflakies-maven-plugin:2.0.0:detect   -pl swagger/swagger-generator/generator-core -am -Ddt.randomize.rounds=30 -Ddt.detector.original_order.all_must_pass=false

Expected Behavior

Mentioned tests should pass with different orders.

Servicecomb Version

3.3.0

Additional Context

No response

[pem70]

PR at #5018