Exclude target subdir from source for infra pubs

* infra-publications.yaml: Address the "cannot move _out to a
subdirectory of itself" error which prematurely terminates the
infra-publications-publish job.

Change-Id: I091f5e9f6efe3e32295cc139c2db2b5e58c8924c
Merge "Exclude target subdir from source for infra pubs"