[Index Management FTR] Improve delete indices test (elastic#200941)

Closes elastic#192351
Closes elastic#200660
Closes elastic#193599
Closes elastic#192532


## Summary

This PR improves the IM functional test for indices table. In
elastic#192351, the failure most likely
occurred because the webdriver tried to interact with elements that are
no longer in the DOM - in this case the index rows and table. To avoid
this, we are adding a try-catch for `StaleElementReferenceError` in the
`expectIndexIsDeleted` test helper. In
elastic#192351,
elastic#20066, and
elastic#193599, the error most likely
was caused because the check if an index row exists was performed before
the row element was removed from the DOM, therefore it was incorrectly
failing. To fix this, we are adding a retry so that the check is retried
in case it fails.

x-pack/test/functional/page_objects/index_management_page.ts

@@ -221,14 +221,33 @@ export function IndexManagementPageProvider({ getService }: FtrProviderContext)
     },
 
     async expectIndexIsDeleted(indexName: string) {
-      const table = await find.byCssSelector('table');
-      const rows = await table.findAllByTestSubject('indexTableRow');
-      const indexNames: string[] = await Promise.all(
-        rows.map(async (row) => {
-          return await (await row.findByTestSubject('indexTableIndexNameLink')).getVisibleText();
-        })
-      );
-      expect(indexNames.includes(indexName)).to.be(false);
+      try {
+        const table = await find.byCssSelector('table');
+        const rows = await table.findAllByTestSubject('indexTableRow');
+
+        const indexNames = await Promise.all(
+          rows.map(async (row) => {
+            try {
+              return await (
+                await row.findByTestSubject('indexTableIndexNameLink')
+              ).getVisibleText();
+            } catch (error) {
+              // If the current row is stale, it has already been removed
+              if (error.name === 'StaleElementReferenceError') return undefined;
+              throw error; // Rethrow unexpected errors
+            }
+          })
+        ).then((names) => names.filter((name) => name !== undefined));
+
+        expect(indexNames.includes(indexName)).to.be(false);
+      } catch (error) {
+        if (error.name === 'StaleElementReferenceError') {
+          // If the table itself is stale, it means all rows have been removed
+          return; // Pass the test since the table is gone
+        } else {
+          throw error; // Rethrow unexpected errors
+        }
+      }
     },
     async manageIndex(indexName: string) {
       const id = `checkboxSelectIndex-${indexName}`;

x-pack/test_serverless/functional/test_suites/common/management/index_management/indices.ts

@@ -15,6 +15,7 @@ export default ({ getPageObjects, getService }: FtrProviderContext) => {
   const esDeleteAllIndices = getService('esDeleteAllIndices');
   const testIndexName = `index-ftr-test-${Math.random()}`;
   const es = getService('es');
+  const retry = getService('retry');
 
   describe('Indices', function () {
     this.tags(['skipSvlSearch']);
@@ -73,7 +74,9 @@ export default ({ getPageObjects, getService }: FtrProviderContext) => {
       });
       it('can delete index', async () => {
         await pageObjects.indexManagement.confirmDeleteModalIsVisible();
-        await pageObjects.indexManagement.expectIndexIsDeleted(testIndexName);
+        await retry.try(async () => {
+          await pageObjects.indexManagement.expectIndexIsDeleted(testIndexName);
+        });
       });
     });
   });