Fix minor cython warning
Fixes 

```
2023-08-26T19:21:26.6203637Z   warning: /home/runner/work/pandas/pandas/pandas/_libs/writers.pyx:123:50: Unknown type declaration 'Py_ssize_t' in annotation, ignoring
2023-08-26T19:21:26.6253780Z   warning: /home/runner/work/pandas/pandas/pandas/_libs/writers.pyx:123:50: Unknown type declaration 'Py_ssize_t' in annotation, ignoring
2023-08-26T19:21:26.6254699Z   warning: /home/runner/work/pandas/pandas/pandas/_libs/writers.pyx:123:50: Unknown type declaration 'Py_ssize_t' in annotation, ignoring
```
Instead of importing like this can we namespace it? I'm a little wary of how confusing this is with the c type Is that the general way we should be import Py_ssize_t? We import like this in a few places

```bash
% grep -R --include="*.pyx" "from cython cimport Py_ssize_t"
./pandas/_libs/sas.pyx:from cython cimport Py_ssize_t
./pandas/_libs/interval.pyx:from cython cimport Py_ssize_t
./pandas/_libs/join.pyx:from cython cimport Py_ssize_t
./pandas/_libs/byteswap.pyx:from cython cimport Py_ssize_t
./pandas/_libs/properties.pyx:from cython cimport Py_ssize_t
./pandas/_libs/reshape.pyx:from cython cimport Py_ssize_t
./pandas/_libs/missing.pyx:from cython cimport Py_ssize_t
./pandas/_libs/tslibs/fields.pyx:from cython cimport Py_ssize_t
./pandas/_libs/tslibs/tzconversion.pyx:from cython cimport Py_ssize_t
./pandas/_libs/tslibs/parsing.pyx:from cython cimport Py_ssize_t
./pandas/_libs/algos.pyx:from cython cimport Py_ssize_t
./pandas/_libs/internals.pyx:from cython cimport Py_ssize_t
./pandas/_libs/ops.pyx:from cython cimport Py_ssize_t
./pandas/_libs/parsers.pyx:from cython cimport Py_ssize_t
```

(if so might be good for a follow up?) Ah I see. Carry on then - lgtm