Upgrade mockito library to version 1.5

[rodolfomiranda]

After upgrading python to version 3.12, mockito upgraded to version 1.5 and all clienting tests failed. In order to have all the tests pass successfully we had to anchor the mockito version to 1.4.
We need to solve the problem with mockito 1.5 and keep with latests versions.

[kentbull]

This was addressed in #116