Fix upload is permitted without a file being selected

src/app/components/profile/fileUpload/fileUpload.component.ts

@@ -39,6 +39,7 @@ export class DialogFileUploadComponent {
    * Fired when the ok button was pressed
    */
   onOkClicked() {
+    if (this.file) {
       this.errorOccurred = false;
       this.uploading = true;
       this.selfService.changeProfilePicture(this.file).subscribe((response) => {
@@ -60,6 +61,10 @@ export class DialogFileUploadComponent {
           this.errorMessage = 'Failed to upload the profile picture.';
         }
       });
+    } else {
+      this.errorOccurred = true;
+      this.errorMessage = 'Please select a file to upload.';
+    }
   }
 
   /**