Fix TOAST2 tests

[ziotom78]

• [X] Make sure that TOAST2 is installed before testing the framework
• [x] Fix a few asserts in the TOAST2 tests

[marcobortolami]

Is it trying to test toast with python 3.11? If it is the case, then I guess it is why it fails. All the tests are passing for me with python 3.9.16.

[ziotom78]

This should fix #263 . It was due to the change from assert np.allclose to np.testing.assert_allclose, which are not 100% equivalent.