Removing a generation remnant

Author: Caitlin Bales (MSFT)

src/main/java/com/microsoft/graph/models/generated/BasePlannerUserIds.java

@@ -14,7 +14,6 @@
 import com.microsoft.graph.options.*;
 import com.microsoft.graph.serializer.*;
 
-import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.EnumSet;