build: bump i18n from 1.7.1 to 1.8.1 in /Library/Homebrew

Bumps [i18n](https://github.com/svenfuchs/i18n) from 1.7.1 to 1.8.1.
- [Release notes](https://github.com/svenfuchs/i18n/releases)
- [Changelog](https://github.com/ruby-i18n/i18n/blob/master/CHANGELOG.md)
- [Commits](https://github.com/svenfuchs/i18n/compare/v1.7.1...v1.8.1

)

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

Library/Homebrew/Gemfile.lock

@@ -23,7 +23,7 @@ GEM
     hpricot (0.8.6)
     http-cookie (1.0.3)
       domain_name (~> 0.5)
-    i18n (1.7.1)
+    i18n (1.8.1)
       concurrent-ruby (~> 1.0)
     jaro_winkler (1.5.4)
     json (2.3.0)