Add support for random seed in tensornet and tensornet-mps backends

[1tnguyen]

Currently, these 2 backends don't support random seed since cutensornetsamplersample is using a random default seed.

When cutensornetsamplersample allows resetting the seed to a user-defined value, we need to update the backends to support cudaq::set_random_seed.

Enable these tests once this issue is fixed (PR #863): https://github.com/NVIDIA/cuda-quantum/blob/6edf1cdb6081d52075dc04fabc3973b3a0fae04a/unittests/integration/ghz_nisq_tester.cpp#L97