release 0.5.2 uses lagacy StrictVersion that doesn't complaint with pep-0440

[worroc]

0.5.2 is the only release that require elasticsearch>=6

File "...../lib/python3.9/site-packages/aioelasticsearch/connection.py", line 61, in init
if StrictVersion(aiohttp.version).version < (3, 0):
File "/usr/lib/python3.9/distutils/version.py", line 40, in init
self.parse(vstring)
File "/usr/lib/python3.9/distutils/version.py", line 137, in parse
raise ValueError("invalid version number '%s'" % vstring)
ValueError: invalid version number '3.7.4.post0'