ONOS-7152 Buck build of gNMI auto-generated gRPC stubs

Change-Id: I214a1e28aaee456f2d48ddcda1af18619275e863
diff --git a/protocols/gnmi/stub/src/main/proto/COMMIT_ID b/protocols/gnmi/stub/src/main/proto/COMMIT_ID
new file mode 100644
index 0000000..0ac43f2
--- /dev/null
+++ b/protocols/gnmi/stub/src/main/proto/COMMIT_ID
@@ -0,0 +1,2 @@
+https://github.com/openconfig/gnmi/blob/master/proto/gnmi/gnmi.proto
+8a14ac0e9ed67e08988f9913243d89f398454824