[CST-4510] Remove check for entity type param in the import from external source page

src/app/submission/import-external/submission-import-external.component.html

@@ -3,7 +3,6 @@
     <div class="col-md-12">
       <h2 id="header" class="pb-2">{{'submission.import-external.title' + ((label) ? '.' + label : '') | translate}}</h2>
       <ds-submission-import-external-searchbar
-        *ngIf="reload$.value.entity"
         [initExternalSourceData]="reload$.value"
         (externalSourceData) = "getExternalSourceData($event)">
       </ds-submission-import-external-searchbar>
@@ -36,13 +35,7 @@
       </ds-alert>
     </div>
   </div>
-  <div class="row" *ngIf="!reload$.value.entity">
-    <div class="col-md-12">
-      <ds-alert [type]="'alert-warning'">
-        <p class="lead mb-0">{{'submission.import-external.page.noentity' | translate}}</p>
-      </ds-alert>
-    </div>
-  </div>
+
   <div class="row">
     <div class="col-md-12">
       <hr>

src/app/submission/import-external/submission-import-external.component.ts

@@ -20,6 +20,7 @@ import { fadeIn } from '../../shared/animations/fade';
 import { PageInfo } from '../../core/shared/page-info.model';
 import { hasValue, isNotEmpty } from '../../shared/empty.util';
 import { getFinishedRemoteData } from '../../core/shared/operators';
+import { NONE_ENTITY_TYPE } from '../../core/shared/item-relationships/item-type.resource-type';
 
 /**
  * This component allows to submit a new workspaceitem importing the data from an external source.
@@ -127,7 +128,7 @@ export class SubmissionImportExternalComponent implements OnInit, OnDestroy {
       ]).pipe(
       take(1)
     ).subscribe(([entity, sourceId, query]: [string, string, string]) => {
-      this.reload$.next({entity: entity, query: query, sourceId: sourceId});
+      this.reload$.next({entity: entity || NONE_ENTITY_TYPE, query: query, sourceId: sourceId});
       this.selectLabel(entity);
       this.retrieveExternalSources();
     }));

src/assets/i18n/en.json5

@@ -3246,8 +3246,6 @@
 
   "submission.import-external.page.hint": "Enter a query above to find items from the web to import in to DSpace.",
 
-  "submission.import-external.page.noentity": "An entity type must be selected in order to use this page. Select it using the 'Import metadata from an external source' button in 'MyDspace' page.",
-
   "submission.import-external.back-to-my-dspace": "Back to MyDSpace",
 
   "submission.import-external.search.placeholder": "Search the external source",