[#694] remove official support for Python 3.8 and before

These versions of the interpreter were occasionally prone to segmentation
faults when it was left to the garbage collection algorithm to properly
sequence object destruction at interpreter close-down.

Author: d-w-moore

README.md

@@ -5,7 +5,7 @@ Python iRODS Client (PRC)
 
 Currently supported:
 
--   Python 3.6 or later
+-   Python 3.9 or later
 -   Establish a (secure) connection to iRODS
 -   Authenticate via password, GSI, PAM
 -   GenQuery and Specific Queries

setup.py

@@ -29,9 +29,6 @@
     classifiers=[
         "License :: OSI Approved :: BSD License",
         "Development Status :: 5 - Production/Stable",
-        "Programming Language :: Python :: 3.6",
-        "Programming Language :: Python :: 3.7",
-        "Programming Language :: Python :: 3.8",
         "Programming Language :: Python :: 3.9",
         "Programming Language :: Python :: 3.10",
         "Programming Language :: Python :: 3.11",