Bump simplecov from 0.21.0 to 0.21.2 (#15536)

Bumps [simplecov](https://github.com/simplecov-ruby/simplecov) from 0.21.0 to 0.21.2.
- [Release notes](https://github.com/simplecov-ruby/simplecov/releases)
- [Changelog](https://github.com/simplecov-ruby/simplecov/blob/main/CHANGELOG.md)
- [Commits](https://github.com/simplecov-ruby/simplecov/compare/v0.21.0...v0.21.2)

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

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Gemfile.lock

@@ -591,7 +591,7 @@ GEM
     simple_form (5.0.3)
       actionpack (>= 5.0)
       activemodel (>= 5.0)
-    simplecov (0.21.0)
+    simplecov (0.21.2)
       docile (~> 1.1)
       simplecov-html (~> 0.11)
       simplecov_json_formatter (~> 0.1)