Swagger-codegen issue while running maven plugin

Description

I'm trying to run swagger-codegen maven plugin for multiple swagger files in following way.

      <plugin>
            <groupId>io.swagger</groupId>
            <artifactId>swagger-codegen-maven-plugin</artifactId>
            <version>2.3.1</version>
            <executions>
                <execution>
                    <goals>
                        <goal>generate</goal>
                    </goals>
                    <configuration>
                        <inputSpec>${project.basedir}/src/main/resources/publisher-api.yaml</inputSpec>
                        <language>java</language>
                        <configOptions>
                            <sourceFolder>src/main/java</sourceFolder>
                        </configOptions>
                        <generateApiTests>false</generateApiTests>
                        <apiPackage>org.wso2.carbon.apimgt.rest.integration.tests.store.api</apiPackage>
                        <modelPackage>org.wso2.carbon.apimgt.rest.integration.tests.store.model</modelPackage>
                        <invokerPackage>org.wso2.carbon.apimgt.rest.integration.tests.util</invokerPackage>
                        <skipOverwrite>true</skipOverwrite>
                        <library>feign</library>
                        <output>${project.basedir}</output>
                    </configuration>
                </execution>
            </executions>
        </plugin>

But it ends up with below error when running
Is there anything I did wrong in this configuration ?

Start by reproducing the shown swagger-codegen Maven plugin configuration with the referenced publisher-api.yaml and multiple executions. The issue body does not include the claimed error or name a source file or test, so compare the Maven output with the plugin's configuration handling; done means the cause is identified and the documented setup runs successfully.