Bump regexp_parser from 2.8.0 to 2.8.1

Bumps [regexp_parser](https://github.com/ammar/regexp_parser) from 2.8.0 to 2.8.1.
- [Changelog](https://github.com/ammar/regexp_parser/blob/master/CHANGELOG.md)
- [Commits](ammar/regexp_parser@v2.8.0...v2.8.1)

---
updated-dependencies:
- dependency-name: regexp_parser
  dependency-type: indirect
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <[email protected]>

Gemfile.lock

@@ -52,7 +52,7 @@ GEM
       ast (~> 2.4.1)
     public_suffix (4.0.7)
     rainbow (3.1.1)
-    regexp_parser (2.8.0)
+    regexp_parser (2.8.1)
     rexml (3.2.5)
     rspec (3.12.0)
       rspec-core (~> 3.12.0)