Use correct commit hash for xmpp

Author: prefiks

rebar.config

@@ -77,7 +77,7 @@
         {stringprep, ".*", {git, "https://github.com/processone/stringprep", {tag, "1.0.29"}}},
         {if_var_true, stun,
          {stun, ".*", {git, "https://github.com/processone/stun", {tag, "1.2.10"}}}},
-        {xmpp, ".*", {git, "https://github.com/processone/xmpp", "cf43573838ca6340cc6737f6485882d2d662a3ef"}},
+        {xmpp, ".*", {git, "https://github.com/processone/xmpp", "307deb6065476bf102d9a8eeb594524eaed36c13"}},
         {yconf, ".*", {git, "https://github.com/processone/yconf", {tag, "1.0.15"}}}
        ]}.