CI/BLD: Build Failures on CircleCI
Seeing these somewhat regularly now. The cythonize step fails with

    pandas/_libs/reshape.pyx:11:0: 'numpy/float16_t.pxd' not found

Examples:

- https://circleci.com/gh/pandas-dev/pandas/5122#tests/containers/3
- https://circleci.com/gh/pandas-dev/pandas/5176#tests/containers/3

cc @jbrockmendel if you have any ideas