Test null name and empty name

Does not assert on contents of the log message because I could not
deduce how to use LoggerRule to capture the message that was being
logged.

src/test/java/com/nirima/jenkins/plugins/docker/DockerCloudTest.java

@@ -23,6 +23,7 @@
 import org.junit.Assert;
 import org.junit.Rule;
 import org.junit.Test;
+import org.jvnet.hudson.test.Issue;
 import org.jvnet.hudson.test.JenkinsRule;
 
 /**
@@ -48,6 +49,22 @@ public void testConstructor_0_10_2() {
                 null); // dockerHostname
     }
 
+    @Issue("JENKINS-70729") // Warn if cloud name is empty
+    @Test
+    public void testConstructorWithEmptyName() {
+        DockerCloud cloud =
+                new DockerCloud("", new DockerAPI(new DockerServerEndpoint("uri", "credentialsId")), List.of());
+        Assert.assertEquals(cloud.getDisplayName(), "");
+    }
+
+    @Issue("JENKINS-70729") // Warn if cloud name is null
+    @Test
+    public void testConstructorWithNullName() {
+        DockerCloud cloud =
+                new DockerCloud(null, new DockerAPI(new DockerServerEndpoint("uri", "credentialsId")), List.of());
+        Assert.assertEquals(cloud.getDisplayName(), null);
+    }
+
     @Test
     public void globalConfigRoundtrip() throws Exception {