support numpy>=2.0 in econml

[imatiach-msft]

Getting errors when using econml with numpy>=2.0:

/usr/share/miniconda/envs/test/lib/python3.9/site-packages/responsibleai/managers/causal_manager.py:10: in <module>
    from econml.solutions.causal_analysis import CausalAnalysis
/usr/share/miniconda/envs/test/lib/python3.9/site-packages/econml/solutions/causal_analysis/__init__.py:4: in <module>
    from ._causal_analysis import CausalAnalysis
/usr/share/miniconda/envs/test/lib/python3.9/site-packages/econml/solutions/causal_analysis/_causal_analysis.py:13: in <module>
    from numpy.lib.function_base import iterable
E   ModuleNotFoundError: No module named 'numpy.lib.function_base'

numpy.lib.function_base was deprecated with numpy>=2.0 hence econml needs to fix the import to support it

[imatiach-msft]

found this migration guide:
https://numpy.org/devdocs/numpy_2_0_migration_guide.html#numpy-lib-namespace

[imatiach-msft]

sent PR with fix:
#945

[cranedroesch]

hi @imatiach-msft , would you mind sharing how you're running this with numpy 2+? The latest release still uses numpy <2. Your recent PR is to the main branch, and the main branch uses old numpy.

Context: I'd like to get econml working using modern numpy if I can, rather than downgrading the rest of my stack.