Update minitest requirement from = 5.25.1 to = 5.25.4

Updates the requirements on [minitest](https://github.com/minitest/minitest) to permit the latest version.
- [Changelog](https://github.com/minitest/minitest/blob/master/History.rdoc)
- [Commits](minitest/minitest@v5.25.1...v5.25.4)

---
updated-dependencies:
- dependency-name: minitest
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

Gemfile

@@ -6,7 +6,7 @@
 source 'https://rubygems.org'
 ruby '>2.6'
 
-gem 'minitest', '5.25.1'
+gem 'minitest', '5.25.4'
 gem 'pidfile', '0.3.0'
 gem 'rake', '13.2.1'
 gem 'rubocop', '1.50.2'

transcode.gemspec

@@ -24,7 +24,7 @@ Gem::Specification.new do |s|
   s.add_runtime_dependency 'pidfile', '0.3.0'
   s.add_runtime_dependency 'terminal-table', '3.0.2'
   s.add_runtime_dependency 'video_transcoding', '0.25.3'
-  s.add_development_dependency 'minitest', '5.25.1'
+  s.add_development_dependency 'minitest', '5.25.4'
   s.add_development_dependency 'rake', '13.2.1'
   s.add_development_dependency 'rubocop', '1.50.2'
 end