Quietly fail init if no database is present

Failing loudly under these circs context isn't helpful because it
doesn't reflect a problem with the analytics setup; apps in CI often run
the asset precompilation step without a database present.

lib/dfe/analytics.rb

@@ -89,6 +89,8 @@ def self.initialize!
           model.include(DfE::Analytics::Entities)
         end
       end
+    rescue ActiveRecord::ConnectionNotEstablished
+      Rails.logger.info('No database connection; DfE Analytics not initialized')
     end
 
     def self.enabled?

spec/dfe/analytics_spec.rb

@@ -22,6 +22,16 @@
       table
     end
 
+    context 'when no database connection is available' do
+      before do
+        allow(DfE::Analytics::Fields).to receive(:check!).and_raise(ActiveRecord::ConnectionNotEstablished)
+      end
+
+      it 'recovers and logs' do
+        expect { DfE::Analytics.initialize! }.not_to raise_error
+      end
+    end
+
     context 'when the field lists are valid' do
       before do
         allow(DfE::Analytics).to receive(:allowlist).and_return(