[Security] Bump gunicorn from 19.4.1 to 19.9.0

[dependabot-preview]

Bumps gunicorn from 19.4.1 to 19.9.0. This update includes security fixes.

Vulnerabilities fixed

Sourced from The GitHub Security Advisory Database.

Moderate severity vulnerability that affects gunicorn
gunicorn version 19.4.5 contains a CWE-113: Improper Neutralization of CRLF Sequences in HTTP Headers vulnerability in "process_headers" function in "gunicorn/http/wsgi.py" that can result in an attacker causing the server to return arbitrary HTTP headers. This vulnerability appears to have been fixed in 19.5.0.

Affected versions: < 19.5.0

Release notes

Sourced from gunicorn's releases.

19.9.0

• fix: address a regression that prevented syslog support from working
  (#1668, #1773)
• fix: correctly set REMOTE_ADDR on versions of Python 3 affected by
  Python Issue 30205 <https://bugs.python.org/issue30205>_
  (#1755, #1796)
• fix: show zero response length correctly in access log (#1787)
• fix: prevent raising :exc:AttributeError when --reload is not passed
  in case of a :exc:SyntaxError raised from the WSGI application.
  (#1805, #1806)
• ❗️The internal module gunicorn.workers.async was renamed to
  gunicorn.workers.base_async since async is now a reserved word
  in Python 3.7.
  (#1527)

19.8.1

• fix: secure scheme headers when bound to a unix socket (#1766, #1767)

19.8.0

• Eventlet 0.21.0 support (#1584)
• Tornado 5 support (#1728, #1752)
• support watching additional files with --reload-extra-file
  (#1527)
• support configuring logging with a dictionary with --logging-config-dict
  (#1087, #1110, #1602)
• add support for the --config flag in the GUNICORN_CMD_ARGS environment
  variable (#1576, #1581)
• disable SO_REUSEPORT by default and add the --reuse-port setting
  (#1553, #1603, #1669)
• fix: installing inotify on MacOS no longer breaks the reloader
  (#1540, #1541)
• fix: do not throw TypeError when SO_REUSEPORT is not available
  (#1501, #1491)
• fix: properly decode HTTP paths containing certain non-ASCII characters
  (#1577, #1578)
• fix: remove whitespace when logging header values under gevent (#1607)
• fix: close unlinked temporary files (#1327, #1428)
• fix: parse --umask=0 correctly (#1622, #1632)
• fix: allow loading applications using relative file paths
  (#1349, #1481)
• fix: force blocking mode on the gevent sockets (#880, #1616)
• fix: preserve leading / in request path (#1512, #1511)
• fix: forbid contradictory secure scheme headers
• fix: handle malformed basic authentication headers in access log
  (#1683, #1684)
• fix: defer handling of USR1 signal to a new greenlet under gevent
  (#1645, #1651)
• fix: the threaded worker would sometimes close the wrong keep-alive
  connection under Python 2 (#1698, #1699)
• fix: re-open log files on USR1 signal using handler._open to

... (truncated)

Commits

• 29f0394 Release version 19.9.0
• 3e265d4 Regenerate settings documentation
• c7c0f9d Update changelog
• bd833e0 Merge pull request #1796 from diegoholiveira/1795-rename-async-module
• f0c5499 Merge branch 'W7PEA-patch-2'
• 7891310 Use consistent style in nginx.conf
• 101f2da Merge branch 'patch-2' of https://github.com/W7PEA/gunicorn into W7PEA-patch-2
• d213103 Optimize by precompiling regex and using tuple for iterable copies.
• 557b919 Merge branch 'master' into 1795-rename-async-module
• 21f0adc Fix AttributeError when --reload was not passed (#1806)
• Additional commits viewable in compare view

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This change is 

[coveralls]

Coverage remained the same at 71.773% when pulling 3555f5a on dependabot/pip/gunicorn-19.9.0 into 2f1daba on master.

[dependabot-preview]

Superseded by #723.