Update minitest requirement from = 5.10.1 to = 5.15.0

[dependabot[bot]]

Updates the requirements on minitest to permit the latest version.

Changelog

Sourced from minitest's changelog.

=== 5.15.0 / 2021-12-14

• 1 major enhancement:

  • assert_throws returns the value returned, if any. (volmer)

• 3 minor enhancements:

  • Added -S option to skip reporting of certain types of output
  • Enable Ruby deprecation warnings by default. (casperisfine)
  • Use Etc.nprocessors by default in order to maximize cpu usage. (tonytonyjan)

• 6 bug fixes:

  • Close then unlink tempfiles on Windows. (nobu)
  • Fixed #skip_until for windows paths. (MSP-Greg)
  • Fixed a bunch of tests for jruby and windows. (MSP-Greg)
  • Fixed marshalling of specs if they error. (tenderlove, jeremyevans, et al)
  • Updated deprecation message for block expectations. (blowmage)
  • Use Kernel.warn directly in expectations in case CUT defines their own warn. (firien)

=== 5.14.4 / 2021-02-23

• 1 bug fix:

  • Fixed deprecation warning using stub with methods using keyword arguments. (Nakilon)

=== 5.14.3 / 2021-01-05

• 1 bug fix:

  • Bumped require_ruby_version to < 4 (trunk = 3.1).

=== 5.14.2 / 2020-08-31

• 1 bug fix:

  • Bumped ruby version to include 3.0 (trunk).

=== 5.14.1 / 2020-05-15

• 3 minor enhancements:

  • Minitest.filter_backtrace returns original backtrace if filter comes back empty.
  • Minitest::BacktraceFilter now returns entire backtrace if $MT_DEBUG set in env.
  • Return true on a successful refute. (jusleg)

• 1 bug fix:

  • Fixed expectation doco to not use global expectations.

... (truncated)

Commits

• fe3992e prepped for release
• 7136b6e - Fixed #skip_until for windows paths. (MSP-Greg)
• ad135e9 - Fixed marshalling of specs if they error. (tenderlove, jeremyevans, et al)
• fee0bb0 Added minitest-heat to readme. (garrettdimon)
• 53cf9dd Added failing test to show specs can't marshal if they raise. (jeremyevans)
• 0c207e3 - Updated deprecation message for block expectations. (blowmage)
• 118c495 - Use Kernel.warn directly in expectations in case CUT defines their own warn...
• a320274 + Use Etc.nprocessors by default in order to maximize cpu usage. (tonytonyjan)
• 5352c9e + Enable Ruby deprecation warnings by default. (casperisfine)
• 0e1418b Fixed typo for 5.0.0 in History.rdoc. (tnir)
• Additional commits viewable in compare view

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