Fix a typo in roles.yml of the kbn-es package.

[azasypkin]

Summary

Luckily ES ignores invalid role definitions in roles.yml, but it still logs the following error:

node scripts/functional_tests_server.js --config x-pack/test_serverless/api_integration/test_suites/search/config.ts
----
docker logs -f es01
....
[2023-08-31T09:36:55,775][ERROR][o.e.x.s.a.s.FileRolesStore] [es01] invalid role definition [null] in roles file [/usr/share/elasticsearch/config/roles.yml]. skipping role..

[kibana-ci]

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• Commit: 4e850af

Metrics [docs]

✅ unchanged

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@elasticmachine merge upstream