mod_proxy: Fix selection of ProxyPassMatch workers with host/port substitution. PR...

mod_proxy: Fix selection of ProxyPassMatch workers with host/port substitution. PR 69233.

With "ProxyPassMatch ^/([^/]+)/(.*)$ https://$1/$2", ap_proxy_get_worker_ex()
should not consider the length of scheme://host part of the given URL because
of the globbing match on the host part.

Fix it by setting worker->s>is_host_matchable when creating a worker with host
substitution and avoiding the min_match check in worker_matches() in this case.

git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@1919617 13f79535-47bb-0310-9956-ffa450edef68