[Sync EN] eio/constants.xml: add dots at the ends of sentences (#3562)

[github-actions]

Commit: https://github.com/php/doc-en/commit/2132501990f8e139a75021165634830f1f6a90e1
PR: https://github.com/php/doc-en/pull/3562

Archivos ES a actualizar

• reference/eio/constants.xml