Check Runner Token to unset unwanted envvars
While debugging the codebase, I identified a typebug where, when the runner token set is an authentication token, the Runner Pod fails to start due to the presence of some unwanted environment variables:
REGISTER_LOCKED
RUNNER_TAG_LIST
REGISTER_RUN_UNTAGGED
REGISTER_ACCESS_LEVEL
This fix addresses the issue by implementing a check for the use of an authentication token, examining both the registration token and the runner token provided (depending on the available one).