TC_rsl_modify_encr BTS_Tests

Regression

Failing for the past 1 build since #604

Took 11 sec (from Titan)

Stack Trace

"BTS_Tests.ttcn:787 : Timeout expecting RF CHAN REL"
      BTS_Tests.ttcn:9448 BTS_Tests control part
      BTS_Tests.ttcn:7781 TC_rsl_modify_encr testcase