chore(deps): bump gunicorn from 19.7.1 to 20.1.0

[dependabot]

⚠️ Dependabot is rebasing this PR ⚠️

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Bumps gunicorn from 19.7.1 to 20.1.0.

Release notes

Sourced from gunicorn's releases.

20.0.4

• fix binding a socket using the file descriptor
• remove support for the bdist_rpm build

20.0.3

• fixed load of a config file without a Python extension
• fixed socketfromfd.fromfd when defaults are not set

note: we now warn when we load a config file without Python Extension

20.0.2

• fix changelog

20.0.1

• fixed the way the config module is loaded. __file__ is now available
• fixed wsgi.input_terminated. It is always true.
• use the highest protocol version of openssl by default
• only support Python >= 3.5
• added __repr__ method to Config instance
• fixed support of AIX platform and musl libc in socketfromfd.fromfd function
• fixed support of applications loaded from a factory function
• fixed chunked encoding support to prevent any request smuggling <https://portswigger.net/research/http-desync-attacks-request-smuggling-reborn>_
• Capture os.sendfile before patching in gevent and eventlet workers. fix RecursionError.
• removed locking in reloader when adding new files
• load the WSGI application before the loader to pick up all files

note this release add official support for applications loaded from a factory function as documented in Flask and other places.

20.0

• Fixed fdopen RuntimeWarning in Python 3.8
• Added check and exception for str type on value in Response process_headers method.
• Ensure WSGI header value is string before conducting regex search on it.
• Added pypy3 to list of tested environments
• Grouped StopIteration and KeyboardInterrupt exceptions with same body together in Arbiter.run()
• Added setproctitle module to extras_require in setup.py
• Avoid unnecessary chown of temporary files
• Logging: Handle auth type case insensitively
• Removed util.import_module
• Removed fallback for types.SimpleNamespace in tests utils
• Use SourceFileLoader instead instead of execfile_
• Use importlib instead of __import__ and eval`
• Fixed eventlet patching
• Added optional datadog <https://www.datadoghq.com>_ tags for statsd metrics
• Header values now are encoded using latin-1, not ascii.
• Rewritten parse_address util added test
• Removed redundant super() arguments

... (truncated)

Commits

• 61ccfd6 bump to 20.1.0
• d1f0f11 fix inline code syntax in news
• f87882e add an empty line in news.rst
• 7a79808 update changeslog
• 6fd97b9 Document that WEB_CONCURRENCY is set by, at least, Heroku
• dad99a1 Update gunicorn_ext.py
• 3273492 Improve settings documentation
• 86eac4c Merge pull request #2479 from benoitc/capture-peer-name
• 03c642e Merge pull request #2480 from kofrezo/update_docs_install
• a4407ab Default to Python 3 version of gunicorn in Stretch
• Additional commits viewable in compare view

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[dependabot]

The following labels could not be found: pip dependencies.

[ChuckCox]

@dependabot rebase