Update simplecov requirement to ~> 0.13.0

[dependabot-preview]

Updates the requirements on simplecov to permit the latest version.

Release notes

Sourced from simplecov's releases.

v0.13.0

Enhancements

• Faster run times when a very large number of files is loaded into SimpleCov. See #520 (thanks alyssais)
• Only read in source code files that are actually used (faster when files are ignored etc.). See #540 (thanks yui-knk)

Changelog

Sourced from simplecov's changelog.

0.14.0 2017-03-15 (changes)

Enhancements

• Officially support JRuby 9.1+ going forward (should also work with previous releases). See #547 (ping PragTob when encountering issues)
• Add Channel group to Rails profile, when ActionCable is loaded. See #492 (thanks BenMorganIO)
• Stop extending instances of Array and Hash during merging results avoiding problems frozen results while manually merging results. See #558 (thanks aroben)

Bugfixes

• Fix parallel_tests when a thread ends up running no tests. See #533 (thanks cshaffer)
• Skip the :nocov: comments along with the code that they skip. See #551 (thanks ebiven)
• Fix crash when Home environment variable is unset. See #482 (thanks waldyr)
• Make track_files work again when explicitly setting it to nil. See #463 (thanks craiglittle)
• Do not overwrite .last_run.json file when refuse_coverage_drop option is enabled and the coverage has dropped (lead to you being able to just rerun tests and everything was fine). See #553 (thanks Miloshes)

0.13.0 2017-01-25 (changes)

Enhancements

• Faster run times when a very large number of files is loaded into SimpleCov. See #520 (thanks alyssais)
• Only read in source code files that are actually used (faster when files are ignored etc.). See #540 (thanks yui-knk)

Bugfixes

• Fix merging of resultsets if a file is missing on one side. See #513 (thanks hanazuki)
• Fix Ruby 2.4 deprecation warnings by using Integer instead of Fixnum. See #523 (thanks nobu)
• Force Ruby 2 to json 2. See dc7417d50 (thanks amatsuda)
• Various other gem dependency fixes for different gems on different ruby versions. (thanks amatsuda)

0.12.0 2016-07-02 (changes)

Enhancements

• Add support for JSON versions 2.x

Bugfixes

• Fix coverage rate of the parallel_tests. See #441 (thanks sinsoku)
• Fix a regression on old rubies that failed to work with the recently introduced frozen VERSION string. See #461 (thanks leafle)

0.11.2 2016-02-03 (changes)

Enhancements

• Do not globally pollute Array and Hash with merge_resultset utility methods. See #449 (thanks amatsuda)
  ... (truncated)

Commits

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[dependabot-preview]

Superseded by #12.