Fix map markers navigation for keyboard users

By using the bindPopup function instead of the click event
popups work when using the keyboard.

Note that now we are loading all the map markers in the first
request in a single query to the database (needed when there
is a lot or markers to show). Because of that we removed the
AJAX endpoint.

app/controllers/budgets/investments_controller.rb

@@ -11,12 +11,11 @@ module Budgets
 
     PER_PAGE = 10
 
-    before_action :authenticate_user!, except: [:index, :show, :json_data]
-    before_action :load_budget, except: :json_data
+    before_action :authenticate_user!, except: [:index, :show]
+    before_action :load_budget
 
-    authorize_resource :budget, except: :json_data
-    load_and_authorize_resource :investment, through: :budget, class: "Budget::Investment",
-                                except: :json_data
+    authorize_resource :budget
+    load_and_authorize_resource :investment, through: :budget, class: "Budget::Investment"
 
     before_action :load_ballot, only: [:index, :show]
     before_action :load_heading, only: [:index, :show]
@@ -25,8 +24,6 @@ module Budgets
     before_action :set_default_investment_filter, only: :index
     before_action :set_view, only: :index
 
-    skip_authorization_check only: :json_data
-
     feature_flag :budgets
 
     has_orders %w[most_voted newest oldest], only: :show
@@ -91,19 +88,6 @@ module Budgets
       super
     end
 
-    def json_data
-      investment = Budget::Investment.find(params[:id])
-      data = {
-        investment_id: investment.id,
-        investment_title: investment.title,
-        budget_id: investment.budget.id
-      }.to_json
-
-      respond_to do |format|
-        format.json { render json: data }
-      end
-    end
-
     private
 
       def resource_model