travis: really fail if the tests fail

When implementing the ssh testing, the move to the script made it so
the first test suite's exit code was ignored. Check whether the main
tests fail and exit with an error in that case.

script/cibuild.sh

@@ -11,6 +11,11 @@ cd _build
 cmake .. -DCMAKE_INSTALL_PREFIX=../_install $OPTIONS
 cmake --build . --target install
 ctest -V .
+ecode=$?
+
+if [ $ecode -ne 0 ]; then
+    exit $ecode
+fi
 
 # Now that we've tested the raw git protocol, let's set up ssh to we
 # can do the push tests over it