Bump rubocop from 1.76.1 to 1.81.1

This release includes some updates in the Style/RedundantParentheses and
Naming/PredicateMethod rules. We're changing the code accordingly.

Bumps [rubocop](https://github.com/rubocop/rubocop) from 1.76.1 to 1.81.1.
- [Release notes](https://github.com/rubocop/rubocop/releases)
- [Changelog](https://github.com/rubocop/rubocop/blob/master/CHANGELOG.md)
- [Commits](https://github.com/rubocop/rubocop/compare/v1.76.1...v1.81.1)

---
updated-dependencies:
- dependency-name: rubocop
  dependency-version: 1.81.1
  dependency-type: direct:development
  update-type: version-update:semver-minor
...

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

app/helpers/budgets_helper.rb

@@ -16,7 +16,7 @@ module BudgetsHelper
     Budget::Ballot.find_by(user: current_user, budget: @budget)
   end
 
-  def unfeasible_or_unselected_filter
+  def unfeasible_or_unselected_filter?
     ["unselected", "unfeasible"].include?(@current_filter)
   end
 

app/helpers/proposals_dashboard_helper.rb

@@ -89,9 +89,8 @@ module ProposalsDashboardHelper
   end
 
   def new_resources_since_last_login?(resources, new_actions_since_last_login)
-    if resources.present?
+    resources.present? &&
       resources.ids.any? { |id| new_actions_since_last_login.include?(id) }
-    end
   end
 
   def active_resources_for(proposal)