restore empty_kibana after saved objects test

[LeeDr]

Summary

In Jenkins, this test test\functional\apps\management\_mgmt_import_saved_objects.js
is the last one in it's ciGroup7 and so when ciGroup8 is started the before method calls await esArchiver.load('empty_kibana'); But if you just run all tests, or all mangement tests it doesn't load empty_kibana between the groups. Something about the way the _mgmt_import_saved_objects changes the .kibana index causes a very strange failure in the next _index_pattern_filter test (it creates an index pattern successfully but then its gone). I assume that if the tests were re-ordered other tests run after the saved objects test would also fail in a similar way.

It could be that the mgmt saved objects test is doing something to the .kibana index that causes the next problem and should be changed?

This PR just loads the empty_kibana .kibana index at the end of the _mgmt_import_saved_objects test so the next test aren't impacted by it.

    describe('', function() {
      this.tags('ciGroup7');

      loadTestFile(require.resolve('./_create_index_pattern_wizard'));
      loadTestFile(require.resolve('./_index_pattern_create_delete'));
      loadTestFile(require.resolve('./_index_pattern_results_sort'));
      loadTestFile(require.resolve('./_index_pattern_popularity'));
      loadTestFile(require.resolve('./_kibana_settings'));
      loadTestFile(require.resolve('./_scripted_fields'));
      loadTestFile(require.resolve('./_scripted_fields_preview'));
      loadTestFile(require.resolve('./_mgmt_import_saved_objects')); << this test
    });

    describe('', function() {
      this.tags('ciGroup8');

      loadTestFile(require.resolve('./_index_pattern_filter')); << breaks this test
      loadTestFile(require.resolve('./_scripted_fields_filter'));
      loadTestFile(require.resolve('./_import_objects'));
      loadTestFile(require.resolve('./_test_huge_fields'));
      loadTestFile(require.resolve('./_handle_alias'));
      loadTestFile(require.resolve('./_handle_version_conflict'));
    });

Running the _index_pattern_filter test by itself always passes for me, because in that case it starts with empty_kibana index.
But if you put .only on the _mgmt_import_saved_objects and _index_pattern_filter test and run them both then the _index_pattern_filter will fail (without this PR).

Checklist

Delete any items that are not applicable to this PR.

• Any text added follows EUI's writing guidelines, uses sentence case text and includes i18n support
• Documentation was added for features that require explanation or tutorials
• Unit or functional tests were updated or added to match the most common scenarios
• This was checked for keyboard-only and screenreader accessibility
• This renders correctly on smaller devices using a responsive layout. (You can test this in your browser
• This was checked for cross-browser compatibility, including a check against IE11

For maintainers

• This was checked for breaking API changes and was labeled appropriately

[elasticmachine]

Pinging @elastic/kibana-platform (Team:Platform)

[kibanamachine]

💚 Build Succeeded

• continuous-integration/kibana-ci/pull-request
• Commit: 1cb6428

To update your PR or re-run it, just comment with:
@elasticmachine merge upstream

[dmlemeshko]

LGTM
Code review