BUG/MEDIUM: http-ana: Truncate the response when a redirect rule is applied

BUG/MEDIUM: http-ana: Truncate the response when a redirect rule is applied

When a redirect rule is executed on the response path, we must truncate the
received response. Otherwise, the redirect is appended after the response, which
is sent to the client. So it is obviously a bug because the redirect is not
performed. With bodyless responses, it is the "only" bug. But if the response
has a body, the result may be invalid. If the payload is not fully received yet
when the redirect is performed, an internal error is reported.

It must be backported as far as 1.9.