Updating minor incorrectness in asp.net regex

(cherry picked from commit ed9f133)

Author: csanders-git

rules/REQUEST-943-APPLICATION-ATTACK-SESSION-FIXATION.conf

@@ -52,7 +52,7 @@ SecRule REQUEST_COOKIES|!REQUEST_COOKIES:/__utm/|REQUEST_COOKIES_NAMES|ARGS_NAME
     setvar:tx.%{rule.id}-OWASP_CRS/WEB_ATTACK/SESSION_FIXATION-%{matched_var_name}=%{tx.0}"
 
 
-SecRule ARGS_NAMES "@rx ^(jsessionid|aspsessionid|asp.net_sessionid|phpsession|phpsessid|weblogicsession|session_id|session-id|cfid|cftoken|cfsid|jservsession|jwsession)$" \
+SecRule ARGS_NAMES "@rx ^(jsessionid|aspsessionid|asp\.net_sessionid|phpsession|phpsessid|weblogicsession|session_id|session-id|cfid|cftoken|cfsid|jservsession|jwsession)$" \
     "msg:'Possible Session Fixation Attack: SessionID Parameter Name with Off-Domain Referer',\
     phase:2,\
     rev:'2',\