Apply suggestions from code review

Replaced instance calls with static calls as suggested by daniel-beck.
Co-Authored-By: NDaniel Beck <1831569+daniel-beck@users.noreply.github.com>

test/src/test/java/hudson/cli/CancelQuietDownCommandTest.java

@@ -80,7 +80,7 @@ public class CancelQuietDownCommandTest {
 
     @Test
     public void cancelQuietDownShouldSuccessOnQuietDownedJenkins() throws Exception {
-        j.jenkins.get().doQuietDown();
+        j.jenkins.doQuietDown();
         QuietDownCommandTest.assertJenkinsInQuietMode(j);
         final CLICommandInvoker.Result result = command
                 .authorizedTo(Jenkins.READ, Jenkins.ADMINISTER)
@@ -133,7 +133,7 @@ public class CancelQuietDownCommandTest {
         Future<FreeStyleBuild> build = OnlineNodeCommandTest.startBlockingAndFinishingBuild(project, finish);
         assertThat(((FreeStyleProject) j.jenkins.getItem("aProject")).getBuilds(), hasSize(1));
         assertThat(project.isBuilding(), equalTo(true));
-        j.jenkins.get().doQuietDown();
+        j.jenkins.doQuietDown();
         QuietDownCommandTest.assertJenkinsInQuietMode(j);
 
         final CLICommandInvoker.Result result = command
@@ -157,4 +157,4 @@ public class CancelQuietDownCommandTest {
         j.assertBuildStatusSuccess(build);
         QuietDownCommandTest.assertJenkinsNotInQuietMode(j);
     }
-}
\ No newline at end of file
+}

test/src/test/java/hudson/cli/ConnectNodeCommandTest.java

@@ -174,7 +174,7 @@ public class ConnectNodeCommandTest {
     }
 
     @Test public void connectNodeShouldSucceedOnMaster() throws Exception {
-        final Computer masterComputer = j.jenkins.get().getComputer("");
+        final Computer masterComputer = j.jenkins.getComputer("");
 
         CLICommandInvoker.Result result = command
                 .authorizedTo(Computer.CONNECT, Jenkins.READ)

test/src/test/java/hudson/cli/OnlineNodeCommandTest.java

@@ -287,7 +287,7 @@ public class OnlineNodeCommandTest {
     }
 
     @Test public void onlineNodeShouldSucceedOnMaster() throws Exception {
-        final Computer masterComputer = j.jenkins.get().getComputer("");
+        final Computer masterComputer = j.jenkins.getComputer("");
 
         CLICommandInvoker.Result result = command
                 .authorizedTo(Computer.CONNECT, Jenkins.READ)

test/src/test/java/hudson/cli/QuietDownCommandTest.java

@@ -484,7 +484,7 @@ public class QuietDownCommandTest {
     public static final void assertJenkinsInQuietMode(final JenkinsRule j) {
         await().pollInterval(250, TimeUnit.MILLISECONDS)
                 .atMost(10, TimeUnit.SECONDS)
-                .until(() -> j.jenkins.get().getQueue().isBlockedByShutdown(task));
+                .until(() -> j.jenkins.getQueue().isBlockedByShutdown(task));
     }
 
     /**
@@ -494,6 +494,6 @@ public class QuietDownCommandTest {
     public static final void assertJenkinsNotInQuietMode(final JenkinsRule j) {
         await().pollInterval(250, TimeUnit.MILLISECONDS)
                 .atMost(10, TimeUnit.SECONDS)
-                .until(() -> !j.jenkins.get().getQueue().isBlockedByShutdown(task));
+                .until(() -> !j.jenkins.getQueue().isBlockedByShutdown(task));
     }
 }