Skip redis tests if unable to communicate with the server. If the redis module is in the test environment, the redis tests will not be skipped. If connecting to redis during testing fails with a ConnectionError because there is no redis server at localhost, or if it fails with an AuthenticationError, you would fail a slew of tests. This causes the tests to report as skipped if either of the two errors occurs. It is very inefficient as it fails in setup() for the tests, but at least it does report skipping the tests. Also documented how to pass the redis password to the tests in the test part of the install docs. Future note: running tests needs proper docs in development.txt (including database setup) and a link left to that doc in installation.txt.

# human timezones
pytz
# indexer
Whoosh
# xapian is also installed
# extra database support
psycopg2
mysqlclient
redis
# encryption
gpg
# java web tokens
PyJWT
# extra HTTP compression methods
Brotli
zstd
# jinja2 template engine
Jinja2