Migrate from containsAllIn to containsAtLeastElementsIn

The two behave identically, and containsAllIn is being removed.

More information:
  []
Tested:
    TAP --sample for global presubmit queue
    []

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=246565417

javatests/google/registry/model/EntityClassesTest.java

@@ -67,7 +67,9 @@ public class EntityClassesTest {
             .filter(hasAnnotation(EntitySubclass.class))
             .map(Key::getKind)
             .collect(toImmutableSet());
-    assertWithMessage("base entity kinds").that(baseEntityKinds).containsAllIn(entitySubclassKinds);
+    assertWithMessage("base entity kinds")
+        .that(baseEntityKinds)
+        .containsAtLeastElementsIn(entitySubclassKinds);
   }
 
   @Test