Revert 49a7fa to remove fake AWS creds
Revert 49a7fa to remove fake AWS creds

I tested the changes @ImJasonH made in adf030 without these fake aws
credentials and it does appear that the ten minutes slow down we were
observing in https://github.com/tektoncd/pipeline/issues/4087 are fixed.

This PR backs out the phony AWS creds that were in place on the
controller to work around long delays on initial image fetches for
entrypoint lookup (and bundles) related to k8schain.

tektoncd/pipeline,tektoncd/pipeline