build from source issue for 1.1.7

[j-christ]

This is the same issue as reported at: https://forum.image.sc/t/cellprofiler-linux-setup-issue/37507

Complete output from command python setup.py egg_info:
Traceback (most recent call last):
File “”, line 1, in
File “/tmp/pip-build-vbVLHx/centrosome/setup.py”, line 84
**__extkwargs,
^
SyntaxError: invalid syntax

Removing the extra comma after __extkwargs seems to have done the trick.