[BUG] [GO] generated code for specific responses is adding double return statement.

Bug Report Checklist

• Have you provided a full/minimal spec to reproduce the issue?
• Have you validated the input using an OpenAPI validator (example)?
• What's the version of OpenAPI Generator used?
• Have you search for related issues/PRs?
• What's the actual output vs expected output?
• [Optional] Bounty to sponsor the fix (example)

Description

When running the generator for go-experimental in some cases where the paths have specific status codes to return such as CreateImages/ (see https://github.com/outscale/osc-api/blob/3283cc733026d04905905e0d949fea858cee833b/outscale.yaml#L6323) the code generated add double return value to the function and the code results like the following:

https://github.com/marinsalinas/osc-sdk-go/blob/63f74b7d7fe7a6b7716b21167b8acc1824670443/api_image.go#L149

This causes problems with go-vet it marks unreachable code.

openapi-generator version

4.2.0

OpenAPI declaration file content or url

https://raw.githubusercontent.com/outscale/osc-api/master/outscale.yaml

Command line used for generation

openapi-generator generate -i outscale.yaml -g go-experimental

Steps to reproduce

Run the following command:
openapi-generator generate -i outscale.yaml -g go-experimental

you can see the double return statement in oapi_image.go at line 149

Related issues/PRs

Suggest a fix

Remove this double line at:
https://github.com/OpenAPITools/openapi-generator/blob/99204ecd66b61df9d97d5b456a8f82d35febc0e1/modules/openapi-generator/src/main/resources/go-experimental/api.mustache#L334

Start with modules/openapi-generator/src/main/resources/go-experimental/api.mustache at line 334, then reproduce with the outscale.yaml specification and the command openapi-generator generate -i outscale.yaml -g go-experimental. Compare the generated oapi_image.go around line 149; done means the duplicate return is absent and go-vet no longer reports unreachable code.