source LOKI url from profile
Created by: davejrt
Attempting to fix issues where the LOKI url var is empty.
I suspect that because we don't source the variable from the profile, if the logic in the script isn't executed to get the secret, we end up with an empty var when trying to upload.
I don't fully grasp the logic in that upload script, but I hope this keeps the logs flowing and the pipline clean.
fixes https://github.com/sourcegraph/sourcegraph/issues/29053