BSC_Tests: fix vty interface for channel allocator tests

The tests presented in Change I109d986dd7ece1a56422a669ca64353ed46f7ed6,
are using a slightly outdated vty syntax and fail because of that. Lets
update the VTY syntax.

Change-Id: I302e8872dbdc8e65d51902a881f777863de22915
Related: OS#3503
1 file changed