Add and apply Naming/BlockForwarding rubocop rule

This syntax has been added in Ruby 3.1.

Not using a variable name might not be very descriptive, but it's just
as descriptive as using "block" as a variable name. Using just `&` we
get the same amount of information than using `&block`: that we're
passing a block.

We're still using `&action` in `around_action` methods because here we
aren't using a generic name for the variable, so (at least for now) we
aren't running this cop on controllers using `around_action`.

.rubocop.yml

@@ -319,6 +319,13 @@ Lint/UselessAssignment:
 Lint/Void:
   Enabled: true
 
+Naming/BlockForwarding:
+  Enabled: true
+  Exclude:
+    - "app/controllers/application_controller.rb"
+    - "app/controllers/management/base_controller.rb"
+    - "app/controllers/subscriptions_controller.rb"
+
 Naming/VariableName:
   Enabled: true