Add RewriteEngine on directive also in post (#10232)

Fixes
https://github.com/certbot/certbot/issues/9835#issuecomment-2717096178,
where our `RewriteEngine on` directive inserted at the beginning of a
virtualhost was overridden a `RewriteEngine Off` directive later. This
PR does the easy thing of placing `RewriteEngine on` in our
post-insert.

certbot-apache/certbot_apache/_internal/http_01.py

@@ -24,10 +24,10 @@ class ApacheHttp01(common.ChallengePerformer):
     """Class that performs HTTP-01 challenges within the Apache configurator."""
 
     CONFIG_TEMPLATE24_PRE = """\
-        RewriteEngine on
         RewriteRule ^/\\.well-known/acme-challenge/([A-Za-z0-9-_=]+)$ {0}/$1 [END]
     """
     CONFIG_TEMPLATE24_POST = """\
+        RewriteEngine on
         <Directory {0}>
             Require all granted
         </Directory>

certbot-apache/certbot_apache/_internal/tests/http_01_test.py

@@ -209,7 +209,7 @@ class ApacheHttp01Test(util.ApacheTest):
         with open(self.http.challenge_conf_post) as f:
             post_conf_contents = f.read()
 
-        assert "RewriteEngine on" in pre_conf_contents
+        assert "RewriteEngine on" in post_conf_contents
         assert "RewriteRule" in pre_conf_contents
 
         assert self.http.challenge_dir in post_conf_contents