Typo in MISPGalaxyCluster.from_dict prevents field blocklist from being checked

[mspinka-r7]

The missing comma between "distribution" and "sharing_group_id" means these two string literals get concatenated into a single string:

>>> blocked_fields = ["distribution" "sharing_group_id"]
>>> print(blocked_fields)
['distributionsharing_group_id']

PyMISP/pymisp/mispevent.py

Line 1445 in ff8834f

blocked_fields = ["distribution" "sharing_group_id"]

No idea how often this can cause an issue, I just noticed it while looking at the source code when working with PyMISP.

[nightcityblade]

Hi, I'd like to work on this. I'll submit a PR shortly.