Bump parallel from 1.20.1 to 1.21.0 (#16736)

Bumps [parallel](https://github.com/grosser/parallel) from 1.20.1 to 1.21.0.
- [Release notes](https://github.com/grosser/parallel/releases)
- [Commits](https://github.com/grosser/parallel/compare/v1.20.1...v1.21.0)

---
updated-dependencies:
- dependency-name: parallel
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

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

Gemfile

@@ -65,7 +65,7 @@ gem 'nsa', '~> 0.2'
 gem 'oj', '~> 3.13'
 gem 'ox', '~> 2.14'
 gem 'parslet'
-gem 'parallel', '~> 1.20'
+gem 'parallel', '~> 1.21'
 gem 'posix-spawn'
 gem 'pundit', '~> 2.1'
 gem 'premailer-rails'

Gemfile.lock

@@ -397,7 +397,7 @@ GEM
       mime-types
       mimemagic (~> 0.3.0)
       terrapin (~> 0.6.0)
-    parallel (1.20.1)
+    parallel (1.21.0)
     parallel_tests (3.7.1)
       parallel
     parser (3.0.2.0)
@@ -739,7 +739,7 @@ DEPENDENCIES
   omniauth-saml (~> 1.10)
   ox (~> 2.14)
   paperclip (~> 6.0)
-  parallel (~> 1.20)
+  parallel (~> 1.21)
   parallel_tests (~> 3.7)
   parslet
   pg (~> 1.2)