Maintenance: Update dependency rubocop-capybara to v2.21.0

Gemfile.lock

@@ -554,7 +554,7 @@ GEM
       unicode-display_width (>= 2.4.0, < 3.0)
     rubocop-ast (1.31.3)
       parser (>= 3.3.1.0)
-    rubocop-capybara (2.20.0)
+    rubocop-capybara (2.21.0)
       rubocop (~> 1.41)
     rubocop-factory_bot (2.26.1)
       rubocop (~> 1.61)