Temporarily make failed TINC tests more verbose.

In order to debug the MM_gpexpand_2 test failure. TINC prints the full
exception in the TINC log, I think, but I have no access to the log on
the CI machine, and I have not been able to run these tests locally.

src/test/tinc/tinctest/models/scenario/__init__.py

@@ -156,8 +156,9 @@ class _ScenarioStep(object):
                     continue
                 tinctest.logger.error("Worker %s failed execution \n %s" %(ret[0], ret[1]))
                 error_msg = ''
-                if ret[1] and len(ret[1].split('\n')) >= 2:
-                    error_msg = ret[1].split('\n')[-2]
+                #if ret[1] and len(ret[1].split('\n')) >= 2:
+                #    error_msg = ret[1].split('\n')[-2]
+                error_msg = ret[1]
                 if self.fail_fast:
                     raise ScenarioExecutionException("Failing step at the first failure. Worker %s failed execution : %s\n" %(ret[0], error_msg))
                 else: