Bump werkzeug from 0.15.2 to 0.15.3

[dependabot]

⚠️ Dependabot is rebasing this PR ⚠️

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Bumps werkzeug from 0.15.2 to 0.15.3.

Release notes

Sourced from werkzeug's releases.

0.15.3

• Blog: https://palletsprojects.com/blog/werkzeug-0-15-3-released/
• Changes: https://werkzeug.palletsprojects.com/en/0.15.x/changes/#version-0-15-3

Changelog

Sourced from werkzeug's changelog.

Version 0.15.3

Released 2019-05-14

• Properly handle multi-line header folding in development server in
  Python 2.7. (:issue:1080)
• Restore the response argument to :exc:~exceptions.Unauthorized.
  (:pr:1527)
• :exc:~exceptions.Unauthorized doesn't add the WWW-Authenticate
  header if www_authenticate is not given. (:issue:1516)
• The default URL converter correctly encodes bytes to string rather
  than representing them with b''. (:issue:1502)
• Fix the filename format string in
  :class:~middleware.profiler.ProfilerMiddleware to correctly handle
  float values. (:issue:1511)
• Update :class:~middleware.lint.LintMiddleware to work on Python 3.
  (:issue:1510)
• The debugger detects cycles in chained exceptions and does not time
  out in that case. (:issue:1536)
• When running the development server in Docker, the debugger security
  pin is now unique per container.

Commits

• 9b1123a release version 0.15.3
• 00bc43b unique debugger pin in Docker containers
• 2cbdf2b Merge pull request #1542 from asottile/exceptions_arent_always_hashable
• 0e669f6 Fix unhashable exception types
• bdc17e4 Merge pull request #1540 from pallets/break-tb-cycle
• 44e38c2 break cycle in chained exceptions
• 777500b Merge pull request #1518 from NiklasMM/fix/1510_lint-middleware-python3-compa...
• e00c7c2 Make LintMiddleware Python 3 compatible and add tests
• d590cc7 Merge pull request #1539 from pallets/profiler-format
• 0388fc9 update filename_format for ProfilerMiddleware.
• Additional commits viewable in compare view

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