HTTP ERROR 404 | Maven: Build do zero a web | Alura

Boa noite!

Segue abaixo o código utilizado: 1- esse é o código da Classe ContatoServlet

package br.com.alura.maven.lojaweb;

import java.io.IOException;
import java.io.PrintWriter;

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

@WebServlet(urlPatterns={"/contato"})
public class ContatoServlet extends HttpServlet {

    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        PrintWriter writer = resp.getWriter();
        writer.println("<html><h2>Entre em contato</h2></html>");
        writer.close();
    }
}

e agora o código do arquivo 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 http://maven.apache.org/maven-v4_0_0.xsd">
  <modelVersion>4.0.0</modelVersion>
  <groupId>br.com.alura.maven</groupId>
  <artifactId>lojaweb</artifactId>
  <packaging>war</packaging>
  <version>1.0.0-SNAPSHOT</version>
  <name>lojaweb Maven Webapp</name>
  <url>http://maven.apache.org</url>
  <dependencies>
    <dependency>
      <groupId>junit</groupId>
      <artifactId>junit</artifactId>
      <version>3.8.1</version>
      <scope>test</scope>
    </dependency>
    <dependency>
           <groupId>javax.servlet</groupId>
        <artifactId>javax.servlet-api</artifactId>
        <version>3.1.0</version>
    </dependency>
      </dependencies>
  <build>
    <finalName>lojaweb</finalName>
    <plugins>
        <plugin>
          <groupId>org.eclipse.jetty</groupId>
          <artifactId>jetty-maven-plugin</artifactId>
          <version>9.3.7.v20160115</version>
          <configuration>
            <scanIntervalSeconds>10</scanIntervalSeconds>
            <webApp>
                <contextPath>/loja</contextPath>
               </webApp>
              </configuration>
        </plugin>    
    </plugins>
  </build>
</project>