Add query for bug 1248757

This is slightly different than bug 1253896 and this query doesn't show
up in logs where 1253896 shows up, whereas "EOF in transport thread"
shows up in both so we can't fingerprint on that.

I also couldn't find anything in syslog, n-cpu or neutron logs related
to paramiko/transport/connection/ssh failures.

Related-Bug: #1248757

Change-Id: Ib54a1b25e03ed13524058c69a93eef7aa21f3872
Merge "Add query for bug 1248757"