Do not use NotImplementedError

Instead use NoMethodError as to indicate that the method should be
defined in the class

Closes varvet#775

CHANGELOG.md

@@ -2,7 +2,7 @@
 
 ## Unreleased
 
-Nothing.
+- Policy generator uses `NoMethodError` to indicate `#resolve` is not implemented (#776)
 
 ## 2.3.1 (2023-07-17)
 

lib/generators/pundit/install/templates/application_policy.rb

@@ -43,7 +43,7 @@ def initialize(user, scope)
     end
 
     def resolve
-      raise NotImplementedError, "You must define #resolve in #{self.class}"
+      raise NoMethodError, "You must define #resolve in #{self.class}"
     end
 
     private

spec/generators_spec.rb

@@ -35,7 +35,7 @@
       describe "#resolve" do
         it "raises a descriptive error" do
           scope = WidgetPolicy::Scope.new(double("User"), double("User.all"))
-          expect { scope.resolve }.to raise_error(NotImplementedError, /WidgetPolicy::Scope/)
+          expect { scope.resolve }.to raise_error(NoMethodError, /WidgetPolicy::Scope/)
         end
       end
     end