[Enterprise Search] Import correct exception identifier (#161935)

## Summary

The access control deletion function was importing the wrong
`isIndexNotFoundException` to identify when an index doesn't exist. This
would cause index deletion to fail if a search index is missing an
access control index.

x-pack/plugins/enterprise_search/server/lib/indices/delete_access_control_index.test.ts

@@ -0,0 +1,91 @@
+/*
+ * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
+ * or more contributor license agreements. Licensed under the Elastic License
+ * 2.0; you may not use this file except in compliance with the Elastic License
+ * 2.0.
+ */
+
+import { IScopedClusterClient } from '@kbn/core/server';
+
+import { ElasticsearchResponseError } from '../../utils/identify_exceptions';
+
+import { deleteAccessControlIndex } from './delete_access_control_index';
+
+describe('deleteAccessControlIndex lib function', () => {
+  const mockClient = {
+    asCurrentUser: {
+      indices: {
+        delete: jest.fn(),
+      },
+    },
+    asInternalUser: {},
+  };
+
+  beforeEach(() => {
+    jest.clearAllMocks();
+  });
+
+  describe('when ACL index exists', () => {
+    it('should delete index', async () => {
+      mockClient.asCurrentUser.indices.delete.mockImplementation(() => true);
+      await expect(
+        deleteAccessControlIndex(mockClient as unknown as IScopedClusterClient, 'indexName')
+      ).resolves.toEqual(true);
+      expect(mockClient.asCurrentUser.indices.delete).toHaveBeenCalledWith({
+        index: 'indexName',
+      });
+    });
+  });
+
+  describe('when ACL index is missing', () => {
+    const mockErrorRejection: ElasticsearchResponseError = {
+      meta: {
+        body: {
+          error: {
+            type: 'index_not_found_exception',
+          },
+        },
+        statusCode: 404,
+      },
+      name: 'ResponseError',
+    };
+
+    it('exits gracefully', async () => {
+      mockClient.asCurrentUser.indices.delete.mockImplementation(() => {
+        return Promise.reject(mockErrorRejection);
+      });
+      await expect(
+        deleteAccessControlIndex(mockClient as unknown as IScopedClusterClient, 'indexName')
+      ).resolves.not.toThrowError();
+      expect(mockClient.asCurrentUser.indices.delete).toHaveBeenCalledWith({
+        index: 'indexName',
+      });
+    });
+  });
+
+  describe('when index exists but another error is thrown', () => {
+    const mockErrorRejection: ElasticsearchResponseError = {
+      meta: {
+        body: {
+          error: {
+            type: 'uncaught_exception',
+          },
+        },
+        statusCode: 500,
+      },
+      name: 'ResponseError',
+    };
+
+    it('throws the error', async () => {
+      mockClient.asCurrentUser.indices.delete.mockImplementation(() => {
+        return Promise.reject(mockErrorRejection);
+      });
+      await expect(
+        deleteAccessControlIndex(mockClient as unknown as IScopedClusterClient, 'indexName')
+      ).rejects.toEqual(mockErrorRejection);
+      expect(mockClient.asCurrentUser.indices.delete).toHaveBeenCalledWith({
+        index: 'indexName',
+      });
+    });
+  });
+});

x-pack/plugins/enterprise_search/server/lib/indices/delete_access_control_index.ts

@@ -5,14 +5,14 @@
  * 2.0.
  */
 
-import { isIndexNotFoundException } from '@kbn/core-saved-objects-migration-server-internal';
 import { IScopedClusterClient } from '@kbn/core/server';
 
 import { CONNECTORS_ACCESS_CONTROL_INDEX_PREFIX } from '../../../common/constants';
+import { isIndexNotFoundException } from '../../utils/identify_exceptions';
 
 export const deleteAccessControlIndex = async (client: IScopedClusterClient, index: string) => {
   try {
-    await client.asCurrentUser.indices.delete({
+    return await client.asCurrentUser.indices.delete({
       index: index.replace('search-', CONNECTORS_ACCESS_CONTROL_INDEX_PREFIX),
     });
   } catch (e) {