Fix the issue with the `check_shape()` function.

The function check_shape() in minterpy.core.verification is refactored into two separate functions:

• check_shape(): check the expected shape of a given array
• check_dimensionality(): check the expected dimensionality of a given array

This MR should fix Issue #131 (closed).

Additional changes:

• The usage of the function check_shape() in the code base is updated; if only dimensionality should be enforced then check_dimensionality() is used.
• The test suite of MultiIndexSet is updated to include testing the behavior where a given exponents array is not two-dimensional.
• The tests for MultiIndexSet related to default initialization and from_degree() initialization are updated with grouping based on class.
• The tests for verification functions are updated with grouping based on class.