Simplify License#load_license method

app/models/license.rb

@@ -204,7 +204,7 @@ class License < ActiveRecord::Base
     end
 
     def load_license
-      return unless ActiveRecord::Base.connection.table_exists?(:licenses)
+      return unless self.table_exists?
 
       license = self.last
 

spec/models/license_spec.rb

@@ -273,8 +273,7 @@ describe License do
     describe ".current" do
       context 'when licenses table does not exist' do
         before do
-          allow(ActiveRecord::Base.connection).to receive(:table_exists?)
-            .with(:licenses).and_return(false)
+          allow(described_class).to receive(:table_exists?).and_return(false)
         end
 
         it 'returns nil' do