Hacktoberfest - [JENKINS-62446]Test coverage for tool.maven and tool.mavenGlobalConfig (#1525)

* [JENKINS-62446] Test coverage for tool.maven and tool.mavenGlobalConfig

* Adding todo linked to upstream PR.

Co-authored-by: aHenryJard <ajard@cloudbees.com>

integrations/src/test/java/io/jenkins/plugins/casc/GlobalToolGlobalMavenTest.java

@@ -0,0 +1,43 @@
+package io.jenkins.plugins.casc;
+
+import hudson.ExtensionList;
+import hudson.tasks.Maven;
+import io.jenkins.plugins.casc.misc.ConfiguredWithCode;
+import io.jenkins.plugins.casc.misc.JenkinsConfiguredWithCodeRule;
+import jenkins.model.Jenkins;
+import jenkins.mvn.GlobalMavenConfig;
+import org.junit.Rule;
+import org.junit.Test;
+import org.jvnet.hudson.test.Issue;
+
+import static org.hamcrest.CoreMatchers.is;
+import static org.hamcrest.MatcherAssert.assertThat;
+
+public class GlobalToolGlobalMavenTest {
+
+    @Rule
+    public JenkinsConfiguredWithCodeRule j = new JenkinsConfiguredWithCodeRule();
+
+    @Issue("JENKINS-62446")
+    @Test
+    @ConfiguredWithCode("GlobalToolGlobalMavenTest.yaml")
+    public void mavenGlobalConfigurationShouldBeConfigurable() {
+        final Jenkins jenkins = Jenkins.get();
+        //The one with @Symbol("maven")
+        ExtensionList<Maven.DescriptorImpl> mavenTool = jenkins
+            .getExtensionList(Maven.DescriptorImpl.class);
+
+        assertThat("An installation with 'custom' name should have been configured.",
+            mavenTool.get(0).getInstallations()[0].getName(), is("custom"));
+
+
+        //The one with @Symbol("mavenGlobalConfig") since TODO
+        ExtensionList<GlobalMavenConfig> globalMavenConfig = jenkins
+            .getExtensionList(GlobalMavenConfig.class);
+        //TODO when https://github.com/jenkinsci/jenkins/pull/5008 is merged and released
+        // uncomment the mavenGlobalConfig in the GlobalToolGlobalMavenTest.yaml file and add assertions on configuration
+        // update the since comment above with Jenkins version
+
+    }
+
+}

integrations/src/test/resources/io/jenkins/plugins/casc/GlobalToolGlobalMavenTest.yaml

@@ -0,0 +1,18 @@
+tool:
+  maven:
+    installations:
+      - name: "custom"
+        properties:
+          - installSource:
+              installers:
+                - maven:
+                    id: "3.6.3"
+  # TODO when https://github.com/jenkinsci/jenkins/pull/5008 is merged and released
+  # uncomment below and update test
+  #mavenGlobalConfig:
+  #  globalSettingsProvider:
+  #    filePath:
+  #      path: "/tmp2/.m2"
+  #  settingsProvider:
+  #    filePath:
+  #      path: "/tmp2/settings.xml"