Embedding Python >= 3.8 requires to use the pkgconfig profile python-*-embed.
Try to use it and fallback to non-suffixed name on error.

The Caja.OperationHandle.handle property is added: this gives access to the
effective handle taking the form of a non-zero signed integer that can be
stored in a void pointer. Trying to set this property with an invalid value
raises an exception.
Upon update_file_info_full call, the new Caja.OperationHandle is preset with
a "unique" non-null value generated from an atomic counter. When the python
method returns, the handle value is transmitted to Caja whatever it is:
this fixes the problem of Caja expecting a non-null handle when
CAJA_OPERATION_IN_PROGRESS is returned.

Ref: https://github.com/mate-desktop/python-caja/issues/36