Revert to esc_attr_e() in setup-config.php to prevent a fatal error.
kses.php is not loaded at this point, so esc_url() cannot be used.

props csixty4, JustinSainton.
fixes #23516. see #23334.

git-svn-id: https://core.svn.wordpress.org/trunk@23455 1a063a9b-81f0-0310-95a4-ce76da25c4cd