samples: video: fix flaky tests (#2376)

Fix: GoogleCloudPlatform/java-docs-samples#2334
Fix: GoogleCloudPlatform/java-docs-samples#2335

Author: nnegrey

samples/snippets/src/test/java/com/example/video/DetectFacesGcsIT.java

@@ -45,6 +45,6 @@ public void tearDown() {
   public void testDetectFacesGcs() throws Exception {
     DetectFacesGcs.detectFacesGcs("gs://cloud-samples-data/video/googlework_short.mp4");
     String got = bout.toString();
-    assertThat(got).contains("glasses");
+    assertThat(got).contains("Attribute");
   }
 }

samples/snippets/src/test/java/com/example/video/DetectFacesIT.java

@@ -46,6 +46,6 @@ public void tearDown() {
   public void testDetectFaces() throws Exception {
     DetectFaces.detectFaces("resources/googlework_short.mp4");
     String got = bout.toString();
-    assertThat(got).contains("glasses");
+    assertThat(got).contains("Attribute");
   }
 }

samples/snippets/src/test/java/com/example/video/DetectPersonGcsIT.java

@@ -46,6 +46,6 @@ public void tearDown() {
   public void testDetectPersonGcs() throws Exception {
     DetectPersonGcs.detectPersonGcs("gs://cloud-samples-data/video/googlework_short.mp4");
     String got = bout.toString();
-    assertThat(got).contains("Hair");
+    assertThat(got).contains("Landmark");
   }
 }

samples/snippets/src/test/java/com/example/video/DetectPersonIT.java

@@ -46,6 +46,6 @@ public void tearDown() {
   public void testDetectPerson() throws Exception {
     DetectPerson.detectPerson("resources/googlework_short.mp4");
     String got = bout.toString();
-    assertThat(got).contains("Hair");
+    assertThat(got).contains("Landmark");
   }
 }