Swagger3 Authentication is not generated correctly

#9786 ### Description

Swagger3 code generator has removed authMethod section for each Operation that was available in swagger2
There is a general AuthMethod section but for oauth2 it contains all scopes so it can't be used when generating scope checks for specific operations

Swagger-codegen version

Tested with 3.0.13 & 2.4.8 so see the difference

Swagger declaration file content or url

Swagger2 & 3 files to reproduce the problem:
https://gist.github.com/lindgrenfredrik/0eb76d8ee2cac7066bfefd914632a635

Command line used for generation

java -jar -DdebugOperations=True swagger-codegen-cli.jar generate -l jaxrs-resteasy -i pet_example_2_0.json -o tmp2

java -jar -DdebugOperations=True swagger-codegen-cli-3.0.13.jar generate -l jaxrs-resteasy -i pet_example_3_0.yaml -o tmp3

Start with DefaultGenerator.java and the processOperation refactoring described in the issue, then compare the Swagger 2 and Swagger 3 inputs from the linked gist using the provided generation commands. Inspect the generated src/gen/java/io/swagger/api/PetApi.java; done means operation-level @SecurityRequirement scope values are generated consistently rather than only the complete security-definition scope list.