Deprecation warnings/errors by numpy and numba

[Waelthus]

The usage of some data-type aliases, e.g. np.int, has been deprecated in numpy, we need to change those in picca accordingly to allow running and testing on current numpy versions:

module 'numpy' has no attribute 'int'. np.int was a deprecated alias for the builtin int. To avoid this error in existing code, use int by itself. Doing this will not modify any behavior and is safe. When replacing np.int, you may wish to use e.g. np.int64 or np.int32 to specify the precision. If you wish to review your current use, check the release note link for additional information. The aliases was originally deprecated in NumPy 1.20; for more details and guidance see the original release note at: https://numpy.org/devdocs/release/1.20.0-notes.html#deprecations

Also the usage of numba jit compilation when the nopython option is not supplied will change its default from nopython=False to nopython=True:

/home/runner/work/picca/picca/py/picca/xcf.py:1032: NumbaDeprecationWarning: The 'nopython' keyword argument was not supplied to the 'numba.jit' decorator. The implicit default value for this argument is currently False, but it will be changed to True in Numba 0.59.0. See https://numba.readthedocs.io/en/stable/reference/deprecation.html#deprecation-of-object-mode-fall-back-behaviour-when-using-jit for details.