Fix a buglett in backport 230718; get our selection of brigades correct.

  (tis what happens when our code is this far out-of-sync with trunk, sorry.)

git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/proxy-reqbody-2.0.x@230720 13f79535-47bb-0310-9956-ffa450edef68