Fixed call that build list of Storages to build Host file drop down

Issue was introduced in #3956, in commit 6df12d1 code that builds Host file drop down was changed `vm.try(:available_iso_names)` was removed and new method `get_iso_options` was added to build the list. Changed to get all storages that the vm's host is attached to instead of all of the vm's storages

Fixes https://bugzilla.redhat.com/show_bug.cgi?id=1689369

app/controllers/mixins/actions/vm_actions/reconfigure.rb

@@ -233,8 +233,8 @@ def get_vlan_options(host_id)
         def get_iso_options(vm)
           iso_options = []
 
-          datastore_ids = vm.storages.pluck(:id)
-          # determine available iso files for the datastaores
+          datastore_ids = vm.host.storages.pluck(:id)
+          # determine available iso files for the datastores
           Rbac.filtered(StorageFile.where("storage_id IN (?) and ext_name = 'iso'", datastore_ids)).each do |sf|
             iso_options << [sf.name, sf.name + ',' + sf.storage_id.to_s]
           end

spec/controllers/mixins/actions/vm_actions/reconfigure_spec.rb

@@ -0,0 +1,28 @@
+describe Mixins::Actions::VmActions::Reconfigure do
+  describe '#get_iso_options' do
+    before do
+      @vm = FactoryBot.create(:vm_vmware)
+      @host = FactoryBot.create(:host, :name =>'hostname1')
+      @datastore = FactoryBot.create(:storage, :name => 'storage_name')
+      @vm.host = @host
+      FactoryBot.create(:storage_file, :storage_id => @datastore.id, :ext_name => 'iso', :base_name => "good-stuff.iso")
+      FactoryBot.create(:storage_file, :storage_id => 1, :ext_name => 'iso', :base_name => "some_other_storage.iso")
+    end
+
+    context 'populate list of Host files' do
+      let(:controller) { VmInfraController.new }
+
+      it "gets list of VM's host storages that have iso files" do
+        @host.storages << @datastore
+        storage_list = controller.send(:get_iso_options, @vm)
+        expect(storage_list.count).to be(1)
+      end
+
+      it "gets empty list for VM's storage" do
+        @vm.storages << @datastore
+        storage_list = controller.send(:get_iso_options, @vm)
+        expect(storage_list.count).to be(0)
+      end
+    end
+  end
+end