Update bundler requirement from ~> 1.7 to ~> 2.1

[dependabot-preview]

Updates the requirements on bundler to permit the latest version.

Release notes

Sourced from bundler's releases.

v2.1.0

Features:

• Add support for new default gems. In particular,

  • open3 #7455
  • cgi: #7456
  • uri #7460

  plus other PRs removing or lazily loading usages of these gems from other places to not interfere with user's choice, such as #7471 or #7473

Bugfixes:

• Fix bundle exec rake install failing #7474
• Fix bundle exec'ing to rubygems being silent #7442
• Restore previous BUNDLE_GEMFILE in bundler/inline #7418
• Fix error when using gem DSL's :glob option for selecting gemspecs from a specific source #7419

Changes:

• bundle config no longer warns when using "old interface" (might be deprecated again in the future) #7475
• bundle update no longer warns when used without arguments (might be deprecated again in the future) #7475

2.1.0.pre.3 (November 12, 2019)

Features:

• Add caller information to some deprecation messages to make them easier to fix #7361
• Reconcile bundle cache vs bundle package everywhere. Now in docs, CLI help and everywhere else bundle cache is the preferred version and bundle package remains as an alias #7389
• Display some basic bundler documentation together with ruby's RDoc based documentation #7394

Bugfixes:

• Fix typos deprecation message and upgrading docs #7374
• Deprecation warnings about taint usage on ruby 2.7 #7385
• Fix --help flag not correctly delegating to man when used with command aliases #7388
• bundle add should cache newly added gems if an application cache exists #7393
• Stop using an insecure folder as a "fallback home" when user home is not defined #7416
• Fix bundler/inline warning about Bundler.root redefinition #7417

2.1.0.pre.2 (September 15, 2019)

Bugfixes:

• Fix bundle clean trying to delete non-existent directory (#7340)
• Fix warnings about keyword argument separation on ruby 2.7 (#7337)

2.1.0.pre.1 (August 28, 2019)

One of the biggest changes in bundler 2.1.0 is that deprecations for upcoming

... (truncated)

Changelog

Sourced from bundler's changelog.

2.1.0.pre.3 (November 12, 2019)

Features:

• Add caller information to some deprecation messages to make them easier to fix #7361
• Reconcile bundle cache vs bundle package everywhere. Now in docs, CLI help and everywhere else bundle cache is the preferred version and bundle package remains as an alias #7389
• Display some basic bundler documentation together with ruby's RDoc based documentation #7394

Bugfixes:

• Fix typos deprecation message and upgrading docs #7374
• Deprecation warnings about taint usage on ruby 2.7 #7385
• Fix --help flag not correctly delegating to man when used with command aliases #7388
• bundle add should cache newly added gems if an application cache exists #7393
• Stop using an insecure folder as a "fallback home" when user home is not defined #7416
• Fix bundler/inline warning about Bundler.root redefinition #7417

2.1.0.pre.2 (September 15, 2019)

Bugfixes:

• Fix bundle clean trying to delete non-existent directory (#7340)
• Fix warnings about keyword argument separation on ruby 2.7 (#7337)

2.1.0.pre.1 (August 28, 2019)

One of the biggest changes in bundler 2.1.0 is that deprecations for upcoming
breaking changes in bundler 3 will be turned on by default. We do this to grab
feedback and communicate early to our users the kind of changes we're intending
to ship with bundler 3. See
#6965.

Another important improvement is a better coexistence between bundler
installations and the default copy of bundler that comes with ruby installed as
a default gem. Since bundler is shipped as a default gem with ruby, a number of
users have been affected by issues where bundler ends up failing due to version
mismatches, because at some point of the execution, bundler switches to run the
default copy instead of the expected version. A number of PRs have been focused
on minimizing (hopefully eliminating) this, such as
#7100,
#7137,
#6996,
#7056,
#7062,
#7193,
#7216,
#7274

Deprecations:

... (truncated)

Commits

• 4045ba4 Merge #7482
• fc2b63c Merge #7483
• f805835 Fixed test failures with gem command path on ruby core repo.
• 9c26878 Delegate should be supported now
• 935c727 Merge #7480
• 6e2e192 Vendor thor 1.0.0
• f143253 Merge #7478
• 831093c Revert "Write & read dummy gems binarily"
• 3bd06e7 Merge #7477
• 69a88cf Merge #7475
• Additional commits viewable in compare view

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[dependabot-preview]

Superseded by #76.