sua_codec: Adapt test to recent code changes

In 4d6109983b66a5449e119f2cd4b17f18fb06c0c9 we removed a length field
from the sua_msg record, the eunit test case has to be adapted
diff --git a/test/sua_codec_tests.erl b/test/sua_codec_tests.erl
index eace88e..6a6f16e 100644
--- a/test/sua_codec_tests.erl
+++ b/test/sua_codec_tests.erl
@@ -7,7 +7,7 @@
 
 
 -define(MSG_ENC, <<1,0,7,1,0,0,0,208,0,6,0,8,0,0,0,3,1,21,0,8,0,0,0,1,1,2,0,44,0,1,0,7,128,1,0,20,0,0,0,4,12,0,1,4,68,119,121,7,22,0,0,0,128,2,0,8,0,0,8,21,128,3,0,8,0,0,0,7,1,3,0,44,0,1,0,7,128,1,0,20,0,0,0,4,15,0,7,4,8,18,17,9,97,16,81,1,128,2,0,8,0,0,8,22,128,3,0,8,0,0,0,6,1,22,0,8,0,0,0,0,1,11,0,86,98,80,72,4,0,0,32,64,107,26,40,24,6,7,0,17,134,5,1,1,1,160,13,96,11,161,9,6,7,4,0,0,1,0,1,3,108,44,161,42,2,1,0,2,1,2,48,34,4,8,0,1,17,9,97,16,81,241,129,7,145,8,18,1,0,0,242,4,7,145,68,119,121,7,22,0,166,4,128,2,6,192,0,0>>).
--define(MSG_DEC, {sua_msg,1,7,1,204,[{6,{4,<<0,0,0,3>>}},{277,{4,<<0,0,0,1>>}},{258,{40,<<0,1,0,7,128,1,0,20,0,0,0,4,12,0,1,4,68,119,121,7,22,0,0,0,128,2,0,8,0,0,8,21,128,3,0,8,0,0,0,7>>}},{259,{40,<<0,1,0,7,128,1,0,20,0,0,0,4,15,0,7,4,8,18,17,9,97,16,81,1,128,2,0,8,0,0,8,22,128,3,0,8,0,0,0,6>>}},{278,{4,<<0,0,0,0>>}},{267,{82,<<98,80,72,4,0,0,32,64,107,26,40,24,6,7,0,17,134,5,1,1,1,160,13,96,11,161,9,6,7,4,0,0,1,0,1,3,108,44,161,42,2,1,0,2,1,2,48,34,4,8,0,1,17,9,97,16,81,241,129,7,145,8,18,1,0,0,242,4,7,145,68,119,121,7,22,0,166,4,128,2,6,192>>}}]}).
+-define(MSG_DEC, {sua_msg,1,7,1,[{6,{4,<<0,0,0,3>>}},{277,{4,<<0,0,0,1>>}},{258,{40,<<0,1,0,7,128,1,0,20,0,0,0,4,12,0,1,4,68,119,121,7,22,0,0,0,128,2,0,8,0,0,8,21,128,3,0,8,0,0,0,7>>}},{259,{40,<<0,1,0,7,128,1,0,20,0,0,0,4,15,0,7,4,8,18,17,9,97,16,81,1,128,2,0,8,0,0,8,22,128,3,0,8,0,0,0,6>>}},{278,{4,<<0,0,0,0>>}},{267,{82,<<98,80,72,4,0,0,32,64,107,26,40,24,6,7,0,17,134,5,1,1,1,160,13,96,11,161,9,6,7,4,0,0,1,0,1,3,108,44,161,42,2,1,0,2,1,2,48,34,4,8,0,1,17,9,97,16,81,241,129,7,145,8,18,1,0,0,242,4,7,145,68,119,121,7,22,0,166,4,128,2,6,192>>}}]}).
 
 
 dec_test() ->