unittest requires __init__.py for test discovery

GitHub fields:

assignee = None
closed_at = None
created_at = <Date 2021-07-08.15:03:09.936>
labels = ['type-feature', 'library', '3.9']
title = 'unittest requires __init__.py for test discovery'
updated_at = <Date 2021-07-09.01:31:03.042>
user = 'https://bugs.python.org/ma19'

bugs.python.org fields:

activity = <Date 2021-07-09.01:31:03.042>
actor = 'methane'
assignee = 'none'
closed = False
closed_date = None
closer = None
components = ['Library (Lib)']
creation = <Date 2021-07-08.15:03:09.936>
creator = 'ma19'
dependencies = []
files = []
hgrepos = []
issue_num = 44586
keywords = []
message_count = 3.0
messages = ['397144', '397145', '397179']
nosy_count = 3.0
nosy_names = ['methane', 'xtreak', 'ma19']
pr_nums = []
priority = 'normal'
resolution = None
stage = None
status = 'open'
superseder = None
type = 'enhancement'
url = 'https://bugs.python.org/issue44586'
versions = ['Python 3.9']