New Ledger Bucket with Create Only Perms + Moving the CI to devnet from berkeley

[svv232]

We have allocated a new read only bucket for the ledger tarball in CI. This is to prevent the file from accidentally being overwritten by another process pushing to the bucket. The approach here was to simply find and replace the old link. I still have to sanity check if this is correct and would appreciate feedback from @dkijania.