Update ONOS to use yang tools version 2.3.0-b3

Change-Id: I09f6ac082804a1e4b9f80732bbebb83596a1f4d7
diff --git a/tools/dev/bin/patch-yang-libs b/tools/dev/bin/patch-yang-libs
index f04f488..a44613d 100755
--- a/tools/dev/bin/patch-yang-libs
+++ b/tools/dev/bin/patch-yang-libs
@@ -3,7 +3,7 @@
 # Patches lib/BUCK file to use locally built YANG tools.
 # -----------------------------------------------------------------------------
 
-BVER=2.3.0-b2
+BVER=2.3.0-b3
 SVER=2.3-SNAPSHOT
 
 YANG_TOOLS_ROOT=${YANG_TOOLS_ROOT:-~/onos-yang-tools}