Refs #36998 - Fix Rails/Pick and Rails/IndexWith cops

These did not show up when running Rubocop from the Foreman checkout,
but do when executed directly from a Katello checkout.

app/mailers/katello/errata_mailer.rb

@@ -50,9 +50,9 @@ def promote_errata(options)
 
     def errata_counts(errata)
       counts = {:total => errata.count}
-      counts.merge(Hash[[:security, :bugfix, :enhancement].collect do |errata_type|
-        [errata_type, errata.send(errata_type).count]
-      end])
+      counts.merge([:security, :bugfix, :enhancement].index_with do |errata_type|
+        errata.send(errata_type).count
+      end)
     end
   end
 end

app/models/katello/concerns/hostgroup_extensions.rb

@@ -123,7 +123,7 @@ def inherited_ancestry_attribute(attribute, facet)
           facet_model = Facets.registered_facets[facet].hostgroup_configuration.model
           value = facet_model.where.not(attribute => nil).joins(:hostgroup).merge(
             ::Hostgroup.where(id: self.ancestor_ids).reorder(ancestry: :desc)
-          ).limit(1).pluck(attribute).first
+          ).pick(attribute)
         end
         value
       end

app/models/katello/concerns/organization_extensions.rb

@@ -79,7 +79,7 @@ def redhat_provider
         end
 
         def redhat_account_number
-          pools.upstream.pluck(:account_number).first
+          pools.upstream.pick(:account_number)
         end
 
         def active_pools_count