[JAVA] "accept" parameter conflicts with internal "accept" variable during generated APIs...

Description

Thanks for this time saving library :)
I was using it to generate some Java code from a Json Schema and it works, but it fails generating an API object, because of a conflict between a parameter and an internal variable. They are both named as accept.
Here the code snippet:

    public ResponseEntity<TermsAndConditionsResponse> termsAndConditionsUsingPOSTWithHttpInfo(OrderData body, String accept) throws RestClientException {
        Object postBody = body;
        // verify the required parameter 'body' is set
        if (body == null) {
            throw new HttpClientErrorException(HttpStatus.BAD_REQUEST, "Missing the required parameter 'body' when calling termsAndConditionsUsingPOST");
        }
        // verify the required parameter 'accept' is set
        if (accept == null) {
            throw new HttpClientErrorException(HttpStatus.BAD_REQUEST, "Missing the required parameter 'accept' when calling termsAndConditionsUsingPOST");
        }
        String path = UriComponentsBuilder.fromPath("/rs/api/v1/termsAndConditions").build().toUriString();
        
        final MultiValueMap<String, String> queryParams = new LinkedMultiValueMap<String, String>();
        final HttpHeaders headerParams = new HttpHeaders();
        final MultiValueMap<String, Object> formParams = new LinkedMultiValueMap<String, Object>();
        if (accept != null)
            headerParams.add("Accept", apiClient.parameterToString(accept));

        final String[] accepts = { 
            "text/html;charset&#x3D;UTF-8", "text/plain"
         };
        final List<MediaType> accept = apiClient.selectHeaderAccept(accepts);
        final String[] contentTypes = { 
            "application/json"
         };
        final MediaType contentType = apiClient.selectHeaderContentType(contentTypes);

        String[] authNames = new String[] {  };

        ParameterizedTypeReference<TermsAndConditionsResponse> returnType = new ParameterizedTypeReference<TermsAndConditionsResponse>() {};
        return apiClient.invokeAPI(path, HttpMethod.POST, queryParams, postBody, headerParams, formParams, accept, contentType, authNames, returnType);
    }

Swagger-codegen version

3.0.35
It happens also with previous versions.

Swagger declaration file content or url

Here the URL

Command line used for generation

Used the maven plugin with this configuration:

        <plugin>
                <groupId>io.swagger.codegen.v3</groupId>
                <artifactId>swagger-codegen-maven-plugin</artifactId>
                <version>3.0.35</version>
                <executions>
                    <execution>
                        <goals>
                            <goal>generate</goal>
                        </goals>
                        <configuration>
                            <inputSpec>${project.basedir}/src/main/resources/api-docs.json</inputSpec>
                            <language>java</language>
                            <library>resttemplate</library>
                            <apiPackage>com.lastminute.rsimoni.flightcatalog</apiPackage>
                            <modelPackage>com.lastminute.rsimoni.flightcatalog.model</modelPackage>
                            <invokerPackage>com.lastminute.rsimoni.flightcatalog.handler</invokerPackage>
                            <generateApis>true</generateApis>
                            <generateApiTests>false</generateApiTests>
                            <generateApiDocumentation>false</generateApiDocumentation>
                            <generateModelTests>false</generateModelTests>
                            <generateModelDocumentation>false</generateModelDocumentation>
                            <generateSupportingFiles>true</generateSupportingFiles>
                            <configOptions>
                                <interfaceOnly>true</interfaceOnly>
                                <dateLibrary>java8</dateLibrary>
                            </configOptions>
                        </configuration>
                    </execution>
                </executions>
            </plugin>

Steps to reproduce

Simply running the plugin

Related issues/PRs

I searched similar issue, but didn't find anything

Suggest a fix/enhancement

Probably a check for conflicting names? But I didn't check the code...

Reproduce the failure by running the Maven plugin with the supplied OpenAPI URL and Java/resttemplate configuration. Inspect the generated Java API method where the parameter and internal variable are both named accept; done means generation completes with compilable Java code and no duplicate local name.