Fix pylint 2.8.0 compatibility

[asherf]

numversion was removed from pkginfo in pylint:
see: pylint-dev/pylint@fbcb27a#diff-42df8bb8e2d7b0a18f0174dcb5f3c60b1cbca5a394c3c7f8c9b33c99fb6cda99L34

The following error shows up if using latest version of pylint & pylint-django:

File "/home/toolchain/.cache/pants/named_caches/pex_root/venvs/short/90e31a6e/lib/python3.7/site-packages/pylint_django/__init__.py", line 6, in <module>
    from pylint_django import plugin
  File "/home/toolchain/.cache/pants/named_caches/pex_root/venvs/short/90e31a6e/lib/python3.7/site-packages/pylint_django/plugin.py", line 5, in <module>
    from pylint_django.checkers import register_checkers
  File "/home/toolchain/.cache/pants/named_caches/pex_root/venvs/short/90e31a6e/lib/python3.7/site-packages/pylint_django/checkers/__init__.py", line 3, in <module>
    from pylint_django.checkers.models import ModelChecker
  File "/home/toolchain/.cache/pants/named_caches/pex_root/venvs/short/90e31a6e/lib/python3.7/site-packages/pylint_django/checkers/models.py", line 11, in <module>
    from pylint_django.utils import node_is_subclass, PY3
  File "/home/toolchain/.cache/pants/named_caches/pex_root/venvs/short/90e31a6e/lib/python3.7/site-packages/pylint_django/utils.py", line 9, in <module>
    from pylint_django.compat import Uninferable
  File "/home/toolchain/.cache/pants/named_caches/pex_root/venvs/short/90e31a6e/lib/python3.7/site-packages/pylint_django/compat.py", line 28, in <module>
    LOAD_CONFIGURATION_SUPPORTED = pylint.__pkginfo__.numversion >= (2, 3)
AttributeError: module 'pylint.__pkginfo__' has no attribute 'numversion'

Signed-off-by: Asher Foa asher@asherfoa.com

[coveralls]

Pull Request Test Coverage Report for Build 1448

• 1 of 1 (100.0%) changed or added relevant line in 1 file are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 86.867%

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Totals
Change from base Build 1437:	0.0%
Covered Lines:	721
Relevant Lines:	830

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💛 - Coveralls

[justinmerrell]

Instead of defaulting to True it could still perform a version check with pylint.pkginfo.version

From pylint 2.8.0 chages:
__pkginfo__ now only contain __version__ (also accessible with pylint.__version__), other meta-information are still accessible with import importlib;metadata.metadata('pylint').

[atodorov]

CI still failing, not sure why it tries to access numversion. Maybe try pylint.__version__.