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] <[email protected]>

Author: dependabot[bot]

Gemfile.lock

@@ -83,7 +83,7 @@ GEM
     parser (3.3.10.0)
       ast (~> 2.4.1)
       racc
-    power_assert (2.0.5)
+    power_assert (3.0.1)
     pp (0.6.3)
       prettyprint
     prettyprint (0.2.0)
@@ -134,7 +134,7 @@ GEM
     rubyzip (2.4.1)
     semver2 (3.4.2)
     stringio (3.1.7)
-    test-unit (3.7.0)
+    test-unit (3.7.1)
       power_assert
     thor (1.4.0)
     thread_safe (0.3.6)