Fixed numerical comparison unit-tests

Fixed a couple of missing assertions that where checked in the unit-tests:
The failures of the unit-tests where:
```
(...)/sm_common/test/numerical_comparisons.cpp:12: Failure
Expected: sm::approximatelyEqual(1.0, 1.0, 0.0) throws an exception of type std::invalid_argument.
  Actual: it throws nothing.
```