test(support): fix any_instance deprecation warning

Changed from the old syntax to the new allow_any_instance_of according to the documentation.

https://www.rubydoc.info/github/rspec/rspec-mocks/RSpec/Mocks/ExampleMethods%3aallow_any_instance_of

spec/lib/update/update_tickets_spec.rb

@@ -5,7 +5,7 @@ describe UpdateTickets do
 
   
   let(:ticket) {
-    Event.any_instance.stub(:geocode).and_return([1,1])
+    allow_any_instance_of(Event).to receive(:geocode).and_return([1,1])
     create(:ticket, :has_card, :has_event)
   }
 

spec/support/contexts/shared_donation_charge_context.rb

@@ -17,11 +17,11 @@ RSpec.shared_context :shared_donation_charge_context do
   let(:campaign) {force_create(:campaign, nonprofit: nonprofit, goal_amount: 500)}
   let(:other_campaign) {force_create(:campaign, nonprofit: other_nonprofit)}
   let(:event) {
-    Event.any_instance.stub(:geocode).and_return([1,1])
+    allow_any_instance_of(Event).to receive(:geocode).and_return([1,1])
     force_create(:event, nonprofit: nonprofit)
   }
   let(:other_event) {
-    Event.any_instance.stub(:geocode).and_return([1,1])
+    allow_any_instance_of(Event).to receive(:geocode).and_return([1,1])
     force_create(:event, nonprofit: other_nonprofit)
   }
   let(:event_discount) {force_create(:event_discount, event: event, percent: 20)}
@@ -46,4 +46,4 @@ RSpec.shared_context :shared_donation_charge_context do
       StripeMock.stop
     end
   }
-end
+end

spec/support/contexts/shared_rd_donation_value_context.rb

@@ -19,7 +19,7 @@ RSpec.shared_context :shared_rd_donation_value_context do
 
   let(:default_edit_token) {'7903e34c-10fe-11e8-9ead-d302c690bee4'}
   before(:each){
-    allow_any_instance_of(Event).to_receive(:geocode).and_return([1,1])
+    allow_any_instance_of(Event).to receive(:geocode).and_return([1,1])
   }