pybind/mgr: disable type checking in diskprediction_local

Disable type checking in the __preprocess function of
diskprediction_local. This function is already collecting a lot of
`type: ignore` comments and adding more is getting difficult due to
the structure of this function. This time we were hitting errors
like:

diskprediction_local/predictor.py:160: error: Value of type "NDArray?[Any]" is not indexable  [index]
diskprediction_local/predictor.py:161: error: "NDArray?[Any]" has no attribute "shape"  [attr-defined]

on python 3.12.

Fixes: https://tracker.ceph.com/issues/78117

Signed-off-by: John Mulligan <jmulligan@redhat.com>