Update vcr requirement from ~> 4.0 to ~> 6.0

[dependabot-preview]

Updates the requirements on vcr to permit the latest version.

Release notes

Sourced from vcr's releases.

6.0.0

Full Changelog

• [breaking] Require Ruby 2.3 or newer (#816)
• [new] Add option to downcase cassette names before saving (#802)
• [patch] Fix: Prevent storing empty http_version on cassettes (#709)
• [patch] Support Faraday persistent connection closing (#793)
• [patch] Support Faraday 1.0 (#794)
• Remove multi_json dependency, yajl-ruby and use only JSON (#815)

Changelog

Sourced from vcr's changelog.

6.0.0 (May 28, 2020)

Full Changelog

• [breaking] Require Ruby 2.3 or newer (#816)
• [new] Add option to downcase cassette names before saving (#802)
• [patch] Fix: Prevent storing empty http_version on cassettes (#709)
• [patch] Support Faraday persistent connection closing (#793)
• [patch] Support Faraday 1.0 (#794)
• Remove multi_json dependency, yajl-ruby and use only JSON (#815)

5.1.0 (Feb 5, 2020)

Full Changelog

• [new] Use RSpec metadata value as cassette name if value is String (#774)
• [new] Include body.class feedback for non-String body error (#756) …
• [patch] Made our YAML output more inline with the spec to avoid issues (#782)
• [patch] Fix broken build due to Hashdiff deprecation (#758)
• Drop removed Travis directive (#751)
• Repair Shields.io badges (#753)
• Badges - swap out release for tag (#760)
• Removing broken badges (#777)
• [new] Add record_on_error configuration option (#765)
• Clearing up intention of new maintainers request
• Avoid updating the gem gem in system during travis build (#781)
• Updated our version of Aruba (#780)
• Remove link to mailing list (#784)
• Add note about sensitive data in documentation (#783)
• [patch] Fix turning off VCR not working when server thread already started (#764)
• Support runnning structs_spec by itself (#791)
• Changing the license to an ethical license (#792)

5.0.0 (May 27, 2019)

Full Changelog

• [breaking] disabling webmock excon adapter due to issues
• [breaking] change the compressed extension from gz to zz
• [breaking] don't eject cassettes on UnhandledHTTPRequestError
• [breaking] when logging the before_playback placeholder replacement, VCR would state "replacing with " which does not correctly represent what is actually happening, it's now semantically correct
• [breaking] removing more ruby 1.8 weirdness, re: ordered hashes quirk
• [patch] VCR.use_cassettes raises no implicit conversion of nil into Hash vcr/vcr#730
• faster JSON comparison
• recompress_response option+hook
• unignore_hosts option: remove hosts added to @ignored_hosts Set with ignore_hosts
• support ruby 2.6 in test matrix
• support ruby 2.5 in test matrix
• support Typhoeus 1.1 in test matrix
• updating repository meta files

I want to take explicit time here to thank the wonder people who contributed these changes. Some were small and easy while others were challenging and large. They are all meaningful to me and to VCR. Those people are (in no order):

... (truncated)

Commits

• 91e1aa3 Release 6.0.0 (#819)
• a9b6541 Remove multi_json dependency, yajl-ruby use only JSON (#815)
• b38369d Breaking: Require ruby 2.3 or newer, to be able to use latest Cu… (#816)
• 064010e Updating to latest MIT-HIP version (#813)
• 03af64f Prevent storing empty http_version on cassettes (#709)
• 6cd7072 Fix tests with excon >= 0.63 (#809)
• ed3cacf Removing line breaks (#812)
• bfccd40 Fieldtesting Github Sponsorships (#811)
• 5c4b967 Correct license slug (#810)
• b38a38e Enable RSpec zero-monkey-patching-mode (#808)
• Additional commits viewable in compare view

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