Use quotation marks to match the new SSID encoding format in the
NEIGHBOR_REP_REQUEST command. In this specific test case, the exact SSID
value did not make any difference for behavior. The previous version
ended up getting decoded as a hexstring after the NEIGHBOR_REP_REQUEST
format change. The new version goes back to the ASCII string version of
"abcdef".
Signed-off-by: David Spinadel <david.spinadel@intel.com>