Chore: Fix broken tests (#6458)

## Motivation for features / changes
Somehow some tests got broken on master and caused nightly to fail

https://github.com/tensorflow/tensorboard/actions/runs/5377348327/jobs/9755711856#step:11:2529

Author: rileyajones

tensorboard/webapp/core/views/layout_test.ts

@@ -86,6 +86,8 @@ describe('layout test', () => {
       dispatchedActions.push(action);
     });
     store.overrideSelector(getSideBarWidthInPercent, 10);
+    // When the runs table is full screen the width is overridden to 100%.
+    store.overrideSelector(getRunsTableFullScreen, false);
   });
 
   afterEach(() => {

tensorboard/webapp/runs/views/runs_table/runs_data_table.ts

@@ -89,15 +89,15 @@ export class RunsDataTable {
   }
 
   getRunIds() {
-    return this.data.map((row) => row.id);
+    return (this.data || []).map((row) => row.id);
   }
 
   allRowsSelected() {
-    return this.data.every((row) => row['selected']);
+    return (this.data || []).every((row) => row['selected']);
   }
 
   someRowsSelected() {
-    return this.data.some((row) => row['selected']);
+    return (this.data || []).some((row) => row['selected']);
   }
 
   onFilterKeyUp(event: KeyboardEvent) {