Dataclass transform should ignore TypeAlias variables

GitHub fields:

assignee = None
closed_at = None
created_at = <Date 2022-03-30.14:49:32.604>
labels = ['type-bug', '3.8', '3.9', '3.10', '3.11', '3.7', 'library']
title = 'Dataclass transform should ignore TypeAlias variables'
updated_at = <Date 2022-04-06.22:47:22.436>
user = 'https://github.com/thomkeh'

bugs.python.org fields:

activity = <Date 2022-04-06.22:47:22.436>
actor = 'thomkeh'
assignee = 'none'
closed = False
closed_date = None
closer = None
components = ['Library (Lib)']
creation = <Date 2022-03-30.14:49:32.604>
creator = 'thomkeh'
dependencies = []
files = []
hgrepos = []
issue_num = 47166
keywords = []
message_count = 5.0
messages = ['416368', '416414', '416426', '416428', '416903']
nosy_count = 5.0
nosy_names = ['eric.smith', 'JelleZijlstra', 'AlexWaygood', 'GBeauregard', 'thomkeh']
pr_nums = []
priority = 'normal'
resolution = None
stage = None
status = 'open'
superseder = None
type = 'behavior'
url = 'https://bugs.python.org/issue47166'
versions = ['Python 3.7', 'Python 3.8', 'Python 3.9', 'Python 3.10', 'Python 3.11']