Increase the number of unit-tests for Tensor

Tensor class is at the core of Aidge framework and should have better tests to try each of its member functions. These tests should include random loops for resilience and test every function individually.

Reviewing Tensor would also allow to

• detect and fix several bug that still remain
• improve the structure for readability
• understand what should be updated in funcitons (remove dupicated code, missing feature...)
• assess consistency of behaviour across functions