Add METADATA to test_serving: Apache2+MIT=NOTICE am: 5b8bbb814c

Change-Id: I82bafa46ac1e102ffafb6cf2246bf7457cceeef1
diff --git a/METADATA b/METADATA
new file mode 100644
index 0000000..d97975c
--- /dev/null
+++ b/METADATA
@@ -0,0 +1,3 @@
+third_party {
+  license_type: NOTICE
+}