Generate war file from Springboot + React application - reactjs

Question

I've tried all the tutorials but no one works out for me. Does anyone know how to do it the right way?
This is my pom.xml
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.6.4</version>
<relativePath/> <!-- lookup parent from repository -->
</parent>
<groupId>procesos</groupId>
<artifactId>springboot-backend</artifactId>
<version>0.0.1-SNAPSHOT</version>
<packaging>war</packaging>
<name>springboot-backend</name>
<description>Gestor procesos de seleccion</description>
<properties>
<java.version>11</java.version>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-data-jpa</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>com.microsoft.sqlserver</groupId>
<artifactId>mssql-jdbc</artifactId>
<scope>runtime</scope>
</dependency>
<dependency>
<groupId>org.projectlombok</groupId>
<artifactId>lombok</artifactId>
<optional>true</optional>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
<dependency>
<groupId>javax.validation</groupId>
<artifactId>validation-api</artifactId>
<version>2.0.1.Final</version>
</dependency>
<dependency>
<groupId>io.jsonwebtoken</groupId>
<artifactId>jjwt</artifactId>
<version>0.9.1</version>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-security</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
</dependency>
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-test</artifactId>
</dependency>
<dependency>
<groupId>org.jetbrains</groupId>
<artifactId>annotations</artifactId>
<version>RELEASE</version>
<scope>compile</scope>
</dependency>
<!-- https://mvnrepository.com/artifact/com.github.eirslett/frontend-maven-plugin -->
<dependency>
<groupId>com.github.eirslett</groupId>
<artifactId>frontend-maven-plugin</artifactId>
<version>1.6</version>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
<configuration>
<excludes>
<exclude>
<groupId>org.projectlombok</groupId>
<artifactId>lombok</artifactId>
</exclude>
</excludes>
</configuration>
</plugin>
<plugin>
<groupId>com.github.eirslett</groupId>
<artifactId>frontend-maven-plugin</artifactId>
<version>1.6</version>
<configuration>
<workingDirectory>frontend</workingDirectory>
<installDirectory>target</installDirectory>
</configuration>
<executions>
<execution>
<id>install node and npm</id>
<goals>
<goal>install-node-and-npm</goal>
</goals>
<configuration>
<nodeVersion>v8.9.4</nodeVersion>
<npmVersion>5.6.0</npmVersion>
</configuration>
</execution>
<execution>
<id>npm install</id>
<goals>
<goal>npm</goal>
</goals>
<configuration>
<arguments>install</arguments>
</configuration>
</execution>
<execution>
<id>npm run build</id>
<goals>
<goal>npm</goal>
</goals>
<configuration>
<arguments>run build</arguments>
</configuration>
</execution>
</executions>
</plugin>
<plugin>
<artifactId>maven-antrun-plugin</artifactId>
<executions>
<execution>
<phase>generate-resources</phase>
<configuration>
<target>
<copy todir="${project.build.directory}/classes/public">
<fileset dir="${project.basedir}/frontend/build"/>
</copy>
</target>
</configuration>
<goals>
<goal>run</goal>
</goals>
</execution>
</executions>
</plugin>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-dependency-plugin</artifactId>
<executions>
<execution>
<phase>package</phase>
<goals>
<goal>copy</goal>
</goals>
<configuration>
<artifactItems>
<artifactItem>
<groupId>com.heroku</groupId>
<artifactId>webapp-runner</artifactId>
<version>9.0.30.0</version>
<destFileName>webapp-runner.jar</destFileName>
</artifactItem>
</artifactItems>
</configuration>
</execution>
</executions>
</plugin>
</plugins>
</build>
</project>
And this is my project structure.
Structure of the project
When building the app this errors shows:
[ERROR] npm ERR! path C:\Users\andres.ms\Documents\amurcia\procesosV2\springboot-backend-v2\frontend\node_modules\.bin\css-has-pseudo.cmd
[ERROR] npm ERR! code EEXIST
[ERROR] npm ERR! Refusing to delete C:\Users\andres.ms\Documents\amurcia\procesosV2\springboot-backend-v2\frontend\node_modules\.bin\css-has-pseudo.cmd: is outside C:\Users\andres.ms\Documents\amurcia\procesosV2\springboot-backend-v2\frontend\node_modules\css-has-pseudo and not a link
[ERROR] npm ERR! File exists: C:\Users\andres.ms\Documents\amurcia\procesosV2\springboot-backend-v2\frontend\node_modules\.bin\css-has-pseudo.cmd
[ERROR] npm ERR! Move it away, and try again.
So im deleting it, running again but always the same error with other .cmd file
The result should be a .war file that contains all, the react and the springboot.