Merge pull request #347 from ruby-i18n/dependabot/bundler/test-unit-3.7.3

Bump test-unit from 3.7.1 to 3.7.3

Author: movermeyer

Gemfile.lock

@@ -134,7 +134,7 @@ GEM
     rubyzip (3.2.2)
     semver2 (3.4.2)
     stringio (3.2.0)
-    test-unit (3.7.1)
+    test-unit (3.7.3)
       power_assert
     thor (1.4.0)
     thread_safe (0.3.6)