pylintrc: backport inclusive language change from Pylint

pylintrc: backport inclusive language change from Pylint

Pylint commit 850c442dbda8d332049971d5c38f82b86da44f1d modified the pylintrc
template to remove the use of the problematic term “blacklist.” This commit
extracts the relevant parts of that and applies it to our code base, removing
the term in the Graphviz tree as well.

When upgrading to a version of Pylint that includes commit
12a76469782fab5c23d78039c4bfb37e3331945a, we should also swap our usage of
extension-pkg-whitelist for extension-pkg-allow-list.