increased ssh timeout based on Enterprise feedback

thanks to @jhallbachner

Author: joshk

lib/travis/worker/job/runner.rb

@@ -172,7 +172,7 @@ def run_script
         def start_session
           announce("Using worker: #{host_name}\n\n")
           retryable(:tries => 5, :sleep => 3) do
-            Timeout.timeout(5) do
+            Timeout.timeout(10) do
               session.connect
             end
           end