Bump test-unit from 3.7.0 to 3.7.1

Bumps [test-unit](https://github.com/test-unit/test-unit) from 3.7.0 to 3.7.1.
- [Release notes](https://github.com/test-unit/test-unit/releases)
- [Commits](test-unit/test-unit@3.7.0...3.7.1)

---
updated-dependencies:
- dependency-name: test-unit
  dependency-version: 3.7.1
  dependency-type: direct:development
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

Gemfile.lock

@@ -117,7 +117,7 @@ GEM
       hashery (~> 2.0)
       ruby-rc4
       ttfunk
-    power_assert (2.0.5)
+    power_assert (3.0.1)
     public_suffix (6.0.2)
     racc (1.8.1)
     rainbow (3.1.1)
@@ -134,7 +134,7 @@ GEM
     sass-listen (4.0.0)
       rb-fsevent (~> 0.9, >= 0.9.4)
       rb-inotify (~> 0.9, >= 0.9.7)
-    test-unit (3.7.0)
+    test-unit (3.7.1)
       power_assert
     traces (0.15.2)
     ttfunk (1.8.0)