[BUG] [JAVA] wrong values with enum variables in path parameters which generated allowableValues with double quote

Created by: yangguangxiadeyun

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?
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Description

wrong values with enum variables in path parameters which generated allowableValues with double quote. I'm expecting path with the path variables to be /dummypath/ACTIVE or /dummypath/DEACTIVATED, but now it generates with allowableValues = "\"ACTIVE\", \"DEACTIVATED\"" and now only /dummypath/"ACTIVE" and /dummypath/"DEACTIVATED" available.

openapi-generator version

4.3.1

OpenAPI declaration file content or url

openapi: 3.0.0
info: 
  title: sample
  version: v1
servers:
  - url: http://localhost
paths:
  "/dummypath/{sample-enum-var}":
    post:
      parameters:
        - name: sample-enum-var
          in: path
          required: true
          schema:
            $ref: "#/components/schemas/sample-enum-var"
      responses:
        "200":
          description: success
components:
  schemas:
    sample-enum-var:
      type: string
      enum:
        - ACTIVE
        - DEACTIVATED

Command line used for generation

mvn clean package

            <plugin>
                <groupId>org.openapitools</groupId>
                <artifactId>openapi-generator-maven-plugin</artifactId>
                <executions>
                    <execution>
                        <id>generate-v0</id>
                        <goals>
                            <goal>generate</goal>
                        </goals>
                        <configuration>
                            <inputSpec>sample.yaml</inputSpec>
                            <generatorName>spring</generatorName>
                            <modelPackage>com.test.model.v0</modelPackage>
                            <apiPackage>com.test.api.v0</apiPackage>
                            <configOptions>
                                <java8>true</java8>
                                <interfaceOnly>true</interfaceOnly>
                                <dateLibrary>legacy</dateLibrary>
                            </configOptions>
                        </configuration>
                    </execution>
                </executions>
            </plugin>

Steps to reproduce

setup the maven project with plugin
run maven command to generate code
check the code generated in path target\generated-sources\openapi\src\main\java\com\test\api\v0\DummypathApi.java

sample api interface generated

/**
 * NOTE: This class is auto generated by OpenAPI Generator (https://openapi-generator.tech) (4.3.1).
 * https://openapi-generator.tech
 * Do not edit the class manually.
 */
package com.test.api.v0;

import com.test.model.v0.SampleEnumVar;
import io.swagger.annotations.*;
import org.springframework.http.HttpStatus;
import org.springframework.http.MediaType;
import org.springframework.http.ResponseEntity;
import org.springframework.validation.annotation.Validated;
import org.springframework.web.bind.annotation.CookieValue;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestBody;
import org.springframework.web.bind.annotation.RequestHeader;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RequestPart;
import org.springframework.web.context.request.NativeWebRequest;
import org.springframework.web.multipart.MultipartFile;

import javax.validation.Valid;
import javax.validation.constraints.*;
import java.util.List;
import java.util.Map;
import java.util.Optional;
@javax.annotation.Generated(value = "org.openapitools.codegen.languages.SpringCodegen", date = "2020-06-24T10:50:17.023+08:00[Asia/Shanghai]")

@Validated
@Api(value = "dummypath", description = "the dummypath API")
public interface DummypathApi {

    default Optional<NativeWebRequest> getRequest() {
        return Optional.empty();
    }

    /**
     * POST /dummypath/{sample-enum-var}
     *
     * @param sampleEnumVar  (required)
     * @return success (status code 200)
     */
    @ApiOperation(value = "", nickname = "dummypathSampleEnumVarPost", notes = "", tags={  })
    @ApiResponses(value = { 
        @ApiResponse(code = 200, message = "success") })
    @RequestMapping(value = "/dummypath/{sample-enum-var}",
        method = RequestMethod.POST)
    default ResponseEntity<Void> dummypathSampleEnumVarPost(@ApiParam(value = "",required=true, allowableValues = "\"ACTIVE\", \"DEACTIVATED\"") @PathVariable("sample-enum-var") SampleEnumVar sampleEnumVar) {
        return new ResponseEntity<>(HttpStatus.NOT_IMPLEMENTED);

    }

}