Fix nil bug in jboss_invoke_deploy.rb

If there is a connection timeout, the module shouldn't access the "code" method because that does not exist.

Verification step(s):

Option 1: You can either do it this way:

- [x] Set up a webserver that times out
- [x] Run the module against that web server to reproduce the issue
- [ ] Run the patched version of the module against that web server
- [ ] Confirm you no longer see the same error.

Option 2: Or you can just do it this way:

- [x] See the diff and confirm that the unpatched version does indeed try to access the 'code' method if res is nil