This change checks for closed iochans related to the log polling
function and will break out of the loop when both channels are closed.
Which is an indicator that the SSM session has been terminated by some
external process. This fixes an issue where Packer hangs, due to the
infinite loop, when an SSM session is killed outside of Packer.
Related to #9442
* Add a test to ensure the proper host is returned when using session_manager
* Add a basic driver test for the validating that the SSMDriver will fail if the plugin is not in the path.
* Add a bunch of hard coded values for testing on port 8081; ssh configs
are set to localhost and 8081
* Add a base drive for communicating with the session manager plugin
* Update step for creating tunnel to actually create SSM session tunnel via driver
