HPCC-10333 Embedded Python may encounter undefined symbols

Due to bugs in the way that Python is build for some distros, it is necessary
to ensure that the libpython library is loaded with RTLD_GLOBAL set.

Signed-off-by: Richard Chapman <rchapman@hpccsystems.com>
Merge pull request #5136 from richardkchapman/python_global

HPCC-10333 Embedded Python may encounter undefined symbols

Reviewed-by: Gavin Halliday <ghalliday@hpccsystems.com>