[VOL-2525] Fixing the OLT app meter removal and optimizing the bandwith profile to meter map with a Multimap

Change-Id: I62b1fe58770df8f1a9e73a4b5bc1dec751d47ad9
diff --git a/app/src/test/java/org/opencord/olt/impl/OltFlowTest.java b/app/src/test/java/org/opencord/olt/impl/OltFlowTest.java
index 8a80ee0..16b407b 100644
--- a/app/src/test/java/org/opencord/olt/impl/OltFlowTest.java
+++ b/app/src/test/java/org/opencord/olt/impl/OltFlowTest.java
@@ -183,7 +183,7 @@
 
     private class MockOltMeterService implements org.opencord.olt.internalapi.AccessDeviceMeterService {
         @Override
-        public ImmutableMap<String, Set<MeterKey>> getBpMeterMappings() {
+        public ImmutableMap<String, Collection<MeterKey>> getBpMeterMappings() {
             return null;
         }