When we added recovery of pause containers in #16352 we called the recovery
function from the plugin factory function. But in our plugin setup protocol, a
plugin isn't ready for use until we call `SetConfig`. This meant that
recovering pause containers was always done with the default
config. Setting up the Docker client only happens once, so setting the wrong
config in the recovery function also means that all other Docker API calls will
use the default config.
Move the `recoveryPauseContainers` call into the `SetConfig`. Fix the error
handling so that we return any error but also don't log when the context is
canceled, which happens twice during normal startup as we fingerprint the
driver.
Tim Gross