ApplicationStatusServlet creates a session for a failed request

Summary

Application Status Servlet creates a session when Hazelcast is not active
Although this is a failing request, we should not create a session for a HTTP 500 response.
This is still considered as an anonymous request and creating a session can be consuming.

Environment

Confluence Data Center

Steps to Reproduce

1. Configure a Confluence Data Center with more than 1 node
2. Configure a load balancer for the data center
3. Trigger a panic mode for one of the nodes
4. Call the /status on that node

Expected Results

The server responds with HTTP 500 with no session created

Actual Results

An HTTP 500 error is returned and the response contains a session header:

HTTP/1.1 500 Internal Server Error
Server: Apache-Coyote/1.1
Set-Cookie: JSESSIONID=319B13A07E775E53BBAD5E72445B2308; Path=/; HttpOnly
Content-Type: text/html
Content-Length: 0
Date: Fri, 04 Nov 2016 11:10:14 GMT
Connection: close

Workaround

No available workarounds at the moment