Fix downgraded help text component

app/views/attribute_help_texts/_tab.html.erb

@@ -72,10 +72,10 @@ See docs/COPYRIGHT.rdoc for more details.
               </td>
               <td>
                 <attribute-help-text
-                  help-text-id="<%= attribute_help_text.id %>"
-                  attribute="'<%= attribute_help_text.attribute_name %>'"
-                  attribute-scope="<%= attribute_help_text.attribute_scope %>"
-                  additional-label="<%= t(:'attribute_help_texts.show_preview') %>">
+                  [help-text-id]="<%= attribute_help_text.id %>"
+                  [attribute]="'<%= attribute_help_text.attribute_name %>'"
+                  [attribute-scope]="'<%= attribute_help_text.attribute_scope %>'"
+                  [additional-label]="'<%= t(:'attribute_help_texts.show_preview') %>'">
                 </attribute-help-text>
               </td>
               <td class="buttons">

frontend/app/angular4-modules.ts

@@ -501,6 +501,9 @@ import {UploadProgressComponent} from 'core-components/common/notifications/uplo
     // Notifications
     NotificationsContainerComponent,
     OpDateTimeComponent,
+
+    // Entries for ng1 downgraded components
+    AttributeHelpTextComponent,
   ]
 })
 export class OpenProjectModule {

frontend/app/components/common/help-texts/attribute-help-text.component.ts

@@ -92,4 +92,7 @@ export class AttributeHelpTextComponent implements OnInit {
   }
 }
 
-opUiComponentsModule.component('attributeHelpText', downgradeComponent({ component: AttributeHelpTextComponent }));
+opUiComponentsModule.directive(
+  'attributeHelpText',
+  downgradeComponent({ component: AttributeHelpTextComponent })
+);