Correct mistaken regex wildcard in .htaccess

Fixes #8578

Signed-off-by: Dan Callahan <dan.callahan@gmail.com>

.htaccess

@@ -63,7 +63,7 @@
   RewriteRule ^\.well-known/caldav /remote.php/dav/ [R=301,L]
   RewriteRule ^remote/(.*) remote.php [QSA,L]
   RewriteRule ^(?:build|tests|config|lib|3rdparty|templates)/.* - [R=404,L]
-  RewriteCond %{REQUEST_URI} !^/.well-known/(acme-challenge|pki-validation)/.*
+  RewriteCond %{REQUEST_URI} !^/\.well-known/(acme-challenge|pki-validation)/.*
   RewriteRule ^(?:\.|autotest|occ|issue|indie|db_|console).* - [R=404,L]
 </IfModule>
 <IfModule mod_mime.c>

lib/private/Setup.php

@@ -490,7 +490,7 @@ class Setup {
 			$content .= "\n  RewriteCond %{REQUEST_FILENAME} !/robots.txt";
 			$content .= "\n  RewriteCond %{REQUEST_FILENAME} !/updater/";
 			$content .= "\n  RewriteCond %{REQUEST_FILENAME} !/ocs-provider/";
-			$content .= "\n  RewriteCond %{REQUEST_URI} !^/.well-known/(acme-challenge|pki-validation)/.*";
+			$content .= "\n  RewriteCond %{REQUEST_URI} !^/\\.well-known/(acme-challenge|pki-validation)/.*";
 			$content .= "\n  RewriteRule . index.php [PT,E=PATH_INFO:$1]";
 			$content .= "\n  RewriteBase " . $rewriteBase;
 			$content .= "\n  <IfModule mod_env.c>";