Fix rspec-mocks stub deprecation warnings

Author: jonatack

spec/mongoid/adapters/mongoid/base_spec.rb

@@ -20,7 +20,9 @@ module Mongoid
 
           context 'with scopes' do
             before do
-              Person.stub :ransackable_scopes => [:active, :over_age]
+              allow(Person)
+              .to receive(:ransackable_scopes)
+              .and_return([:active, :over_age])
             end
 
             it "applies true scopes" do

spec/ransack/adapters/active_record/base_spec.rb

@@ -20,7 +20,9 @@ module ActiveRecord
 
           context 'with scopes' do
             before do
-              Person.stub ransackable_scopes: [:active, :over_age, :of_age]
+              allow(Person)
+              .to receive(:ransackable_scopes)
+              .and_return([:active, :over_age, :of_age])
             end
 
             it 'applies true scopes' do