add usePlaceholders property

Author: Uditi Mehta

app/preprints/my-preprints/template.hbs

@@ -18,6 +18,7 @@
                     @model={{this.model}}
                     @relationshipName='preprints'
                     @pageSize={{10}}
+                    @usePlaceholders={{false}}
                     as |list|
                 >
                     <list.item as |preprint|>

lib/osf-components/addon/components/paginated-list/has-many/component.ts

@@ -33,6 +33,10 @@ export default class PaginatedHasMany extends BaseDataComponent {
         const model = await taskFor(this.getModelTask).perform();
         if (this.usePlaceholders) {
             await taskFor(this.loadRelatedCountTask).perform(reloading);
+            // Don't bother querying if we already know there's nothing there.
+            if (this.totalCount === 0) {
+                return;
+            }
         }
         const items = await model.queryHasMany(
             this.relationshipName,