Installer: Update link to PHP intl away from old PECL package
PHP 5.5 was the last version supported by PECL intl package. Now the
PHP intl extension is used instead.
Bug: T225558
Change-Id: I68cb7a549c899e69da9a8cfea5a69b9acb41e8ae
(cherry picked from commit 7f0f6af2902cb7cf1406df5b8ee8cd12a5a88f1f)