[Sync EN] ext/curl: CURLOPT_TCP_KEEPCNT instead of CURL_TCP_KEEPCNT (#5684)

[github-actions]

Commit: https://github.com/php/doc-en/commit/d0ac0a55fc0606f0c0c2f0b277d7d38699cc025a
PR: https://github.com/php/doc-en/pull/5684

Neue EN-Dateien (noch nicht übersetzt)

• appendices/migration84/constants.xml