mgmt: rename 'datas' to 'data' in FaceStatus and ForwarderStatus

Plural form of 'data' is 'data'.

refs #3955

Change-Id: I225a384c9a9ecf784f8cd55df19d391931619984
diff --git a/tests/unit-tests/mgmt/nfd/forwarder-status.t.cpp b/tests/unit-tests/mgmt/nfd/forwarder-status.t.cpp
index 075e3ec..3d91b30 100644
--- a/tests/unit-tests/mgmt/nfd/forwarder-status.t.cpp
+++ b/tests/unit-tests/mgmt/nfd/forwarder-status.t.cpp
@@ -45,10 +45,10 @@
       .setNMeasurementsEntries(1771725298)
       .setNCsEntries(1264968688)
       .setNInInterests(612811615)
-      .setNInDatas(1843576050)
+      .setNInData(1843576050)
       .setNInNacks(1234)
       .setNOutInterests(952144445)
-      .setNOutDatas(138198826)
+      .setNOutData(138198826)
       .setNOutNacks(4321);
 }