theano compatibility issue with numpy>1.20?

Attempting to import the pymc3 ops causes an error that appears to be related to theano compatibility issues with newer numpy versions. specifically,

```python
from exoplanet_core.pymc3 import ops
```

leads to the error:

```python
---------------------------------------------------------------------------
AttributeError Traceback (most recent call last)
/var/folders/0y/0wb96bc544s1wvz3qvx484qh0000gn/T/ipykernel_62450/835514745.py in
----> 1 from exoplanet_core.pymc3 import ops

~/anaconda/envs/celmech/lib/python3.9/site-packages/exoplanet_core/pymc3/__init__.py in
20
21
---> 22 __set_compiler_flags()
23
24

~/anaconda/envs/celmech/lib/python3.9/site-packages/exoplanet_core/pymc3/__init__.py in __set_compiler_flags()
5
6 def __set_compiler_flags():
----> 7 import theano
8
9 def add_flag(current, new):

~/anaconda/envs/celmech/lib/python3.9/site-packages/Theano-1.0.5-py3.9.egg/theano/__init__.py in
122 from theano.printing import pprint, pp
123
--> 124 from theano.scan_module import (scan, map, reduce, foldl, foldr, clone,
125 scan_checkpoints)
126

~/anaconda/envs/celmech/lib/python3.9/site-packages/Theano-1.0.5-py3.9.egg/theano/scan_module/__init__.py in
39 __contact__ = "Razvan Pascanu "
40
---> 41 from theano.scan_module import scan_opt
42 from theano.scan_module.scan import scan
43 from theano.scan_module.scan_checkpoints import scan_checkpoints

~/anaconda/envs/celmech/lib/python3.9/site-packages/Theano-1.0.5-py3.9.egg/theano/scan_module/scan_opt.py in
58
59 import theano
---> 60 from theano import tensor, scalar
61 from theano.tensor import opt, get_scalar_constant_value, Alloc, AllocEmpty
62 from theano import gof

~/anaconda/envs/celmech/lib/python3.9/site-packages/Theano-1.0.5-py3.9.egg/theano/tensor/__init__.py in
6 import warnings
7
----> 8 from theano.tensor.basic import *
9 from theano.tensor.subtensor import *
10 from theano.tensor.type_other import *

~/anaconda/envs/celmech/lib/python3.9/site-packages/Theano-1.0.5-py3.9.egg/theano/tensor/basic.py in
18 from theano.gof.type import Generic
19
---> 20 from theano.scalar import int32 as int32_t
21 from theano.tensor import elemwise
22 from theano.tensor.var import (AsTensorError, TensorVariable,

~/anaconda/envs/celmech/lib/python3.9/site-packages/Theano-1.0.5-py3.9.egg/theano/scalar/__init__.py in
1 from __future__ import absolute_import, print_function, division
2
----> 3 from .basic import *
4
5 from .basic_scipy import *

~/anaconda/envs/celmech/lib/python3.9/site-packages/Theano-1.0.5-py3.9.egg/theano/scalar/basic.py in
2368 return s
2369
-> 2370 convert_to_bool = Cast(bool, name='convert_to_bool')
2371 convert_to_int8 = Cast(int8, name='convert_to_int8')
2372 convert_to_int16 = Cast(int16, name='convert_to_int16')

~/anaconda/envs/celmech/lib/python3.9/site-packages/Theano-1.0.5-py3.9.egg/theano/scalar/basic.py in __init__(self, o_type, name)
2321 super(Cast, self).__init__(specific_out(o_type), name=name)
2322 self.o_type = o_type
-> 2323 self.ctor = getattr(np, o_type.dtype)
2324
2325 def __str__(self):

~/anaconda/envs/celmech/lib/python3.9/site-packages/numpy/__init__.py in __getattr__(attr)
322
323 if attr in __former_attrs__:
--> 324 raise AttributeError(__former_attrs__[attr])
325
326 if attr == 'testing':

AttributeError: module 'numpy' has no attribute 'bool'.
`np.bool` was a deprecated alias for the builtin `bool`. To avoid this error in existing code, use `bool` by itself. Doing this will not modify any behavior and is safe. If you specifically wanted the numpy scalar type, use `np.bool_` here.
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
```

Start from the exoplanet_core.pymc3 import entry point shown in the traceback and reproduce the failure with Theano 1.0.5 and a NumPy version above 1.20. Check the package's dependency configuration and compatibility tests, if present; done means importing exoplanet_core.pymc3.ops succeeds without the np.bool AttributeError.

Written by the indexing model from the issue text.