[BUG] [Java]Specified ContentType header values generates uncompilable code

Created by: tejasmehta269

Description

Error like below. Error:(126,25) java: variable contentType is already defined in method

openapi-generator version 4.1.0, 4.1.3, 5.1.1

OpenAPI declaration file content or url.

• name: Content-Type in: header description: Replace 'json' with 'xml' if preferred required: true style: simple schema: type: string example: application/json

OpenAPI declaration file content or url

Command line used for generation

Steps to reproduce

Used Maven plugin to re-produce issue. org.openapitools openapi-generator-maven-plugin 5.1.1

Related issues/PRs

Suggest a fix/enhancement

Simillar issue resovled earlier here. https://github.com/OpenAPITools/openapi-generator/pull/7101