Add and apply Naming/PredicateMethod RuboCop 1.76 rule

This rule was introduced in RuboCop 1.76.0 to ensure methods ending
in '?' return boolean.

This commit applies suggested renames and code cleanup:
- Renames 'is_active?' to 'active_class' since it returns a string
- Renames 'parsed_value' to 'in_favor?' and 'is_request_active' to end with '?'
  for boolean semantics
- Skips false positives like 'save', 'auto_labels' or 'save_requiring_finish_signup',
  which are not predicate methods.

app/components/sdg/goals/help_page_component.rb

@@ -11,7 +11,7 @@ class SDG::Goals::HelpPageComponent < ApplicationComponent
 
   private
 
-    def is_active?(goal)
+    def active_class(goal)
       "is-active" if goal.code == 1
     end
 end