[Sync EN] chapters/intro: drop obsolete WDDX and Java integration claims (#5663)

[github-actions]

Commit: https://github.com/php/doc-en/commit/0bae88c19601e7f67ae6a22a8f9aa44cb9342cc1
PR: https://github.com/php/doc-en/pull/5663

Zu aktualisierende DE-Dateien

• chapters/intro.xml