Repository parameter of ArtifactResolver's constructor does not work

[ufolr]

When create ArtifactResolver with custom local repository or custom remote repository mirror, it can't resolve the pom.

This issues can replay with below code:

@Test
public void testResolvePomWithCustomLocalRepo(){
    String localRepo = "D:/Maven/.m2/repo";
    String mavenCenterMirror = "http://mirrors.cloud.tencent.com/nexus/repository/maven-public/";
    ArtifactResolver artifactResolver = new ArtifactResolver(localRepo, mavenCenterMirror);
    File pomFile = new File("src/test/poms/maven-core-3.0.4.pom");
    Assert.assertTrue(pomFile.canRead());
    List<Artifact> artifacts = artifactResolver.resolvePom(pomFile);

    Assert.assertNotNull(artifacts, "artifacts is null");
    for (Artifact artifact : artifacts) {
        Assert.assertNotNull(artifact.getFile(), "Artifact " + artifact + " is not resolved");
    }
}

[ufolr]

Many times, we may custom local maven repo to other location except “~/.m2/repository”.
And also when we can't connect the official maven repo directly or it's very slow to downloading from official repo, such as in a internal network, we need custom the remote repo as a mirror and expect downloading for the mirror.

[ufolr]

I find this is because, in function MavenProject getMavenProject(File pomFile), it always use the default repository

request.setLocalRepository(lrs.createDefaultLocalRepository());
request.setRemoteRepositories(Arrays.asList(new ArtifactRepository[] {lrs.createDefaultRemoteRepository()}.clone()));

The repository set on constructor does not use when request the pom and jar file.

so I make a PR #21 to set the repository to request, it works.