[Security] Bump pyyaml from 3.13 to 5.1

Created by: dependabot-preview[bot]

Bumps pyyaml from 3.13 to 5.1. This update includes security fixes.

Vulnerabilities fixed

Sourced from The GitHub Security Advisory Database.

High severity vulnerability that affects pyyaml In PyYAML before 4.1, the yaml.load() API could execute arbitrary code. In other words, yaml.safe_load is not used.

Affected versions: < 4.2b1

Changelog

Sourced from pyyaml's changelog.

5.1 (2019-03-13)

• https://github-redirect.dependabot.com/yaml/pyyaml/pull/35 -- Some modernization of the test running
• https://github-redirect.dependabot.com/yaml/pyyaml/pull/42 -- Install tox in a virtualenv
• https://github-redirect.dependabot.com/yaml/pyyaml/pull/45 -- Allow colon in a plain scalar in a flow context
• https://github-redirect.dependabot.com/yaml/pyyaml/pull/48 -- Fix typos
• https://github-redirect.dependabot.com/yaml/pyyaml/pull/55 -- Improve RepresenterError creation
• https://github-redirect.dependabot.com/yaml/pyyaml/pull/59 -- Resolves #57, update readme issues link
• https://github-redirect.dependabot.com/yaml/pyyaml/pull/60 -- Document and test Python 3.6 support
• https://github-redirect.dependabot.com/yaml/pyyaml/pull/61 -- Use Travis CI built in pip cache support
• https://github-redirect.dependabot.com/yaml/pyyaml/pull/62 -- Remove tox workaround for Travis CI
• https://github-redirect.dependabot.com/yaml/pyyaml/pull/63 -- Adding support to Unicode characters over codepoint 0xffff
• https://github-redirect.dependabot.com/yaml/pyyaml/pull/65 -- Support unicode literals over codepoint 0xffff
• https://github-redirect.dependabot.com/yaml/pyyaml/pull/75 -- add 3.12 changelog
• https://github-redirect.dependabot.com/yaml/pyyaml/pull/76 -- Fallback to Pure Python if Compilation fails
• https://github-redirect.dependabot.com/yaml/pyyaml/pull/84 -- Drop unsupported Python 3.3
• https://github-redirect.dependabot.com/yaml/pyyaml/pull/102 -- Include license file in the generated wheel package
• https://github-redirect.dependabot.com/yaml/pyyaml/pull/105 -- Removed Python 2.6 & 3.3 support
• https://github-redirect.dependabot.com/yaml/pyyaml/pull/111 -- Remove commented out Psyco code
• https://github-redirect.dependabot.com/yaml/pyyaml/pull/129 -- Remove call to ord in lib3 emitter code
• https://github-redirect.dependabot.com/yaml/pyyaml/pull/143 -- Allow to turn off sorting keys in Dumper
• https://github-redirect.dependabot.com/yaml/pyyaml/pull/149 -- Test on Python 3.7-dev
• https://github-redirect.dependabot.com/yaml/pyyaml/pull/158 -- Support escaped slash in double quotes "/"
• https://github-redirect.dependabot.com/yaml/pyyaml/pull/181 -- Import Hashable from collections.abc
• https://github-redirect.dependabot.com/yaml/pyyaml/pull/256 -- Make default_flow_style=False
• https://github-redirect.dependabot.com/yaml/pyyaml/pull/257 -- Deprecate yaml.load and add FullLoader and UnsafeLoader classes
• https://github-redirect.dependabot.com/yaml/pyyaml/pull/263 -- Windows Appveyor build

Commits

• e471e86 Updates for 5.1 release
• 9141e90 Windows Appveyor build
• d6cbff6 Skip certain unicode tests when maxunicode not > 0xffff
• 69103ba Update .travis.yml to use libyaml 0.2.2
• 91c9435 Squash/merge pull request #105 from nnadeau/patch-1
• 507a464 Make default_flow_style=False
• 07c88c6 Allow to turn off sorting keys in Dumper
• 611ba39 Include license file in the generated wheel package
• 857dff1 Apply FullLoader/UnsafeLoader changes to lib3
• 0cedb2a Deprecate/warn usage of yaml.load(input)
• Additional commits viewable in compare view

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