Fix invalid resource-name isue with empty instance-name
Description
Setting-up a BuildGrid CAS with a remote-storage backend pointing at another CAS service, downloading existing blobs systematically fails with a NOT_FOUND
error. Debugging shows that defining the instance-name as the empty string may lead to invalid ByteStream
resource-names.
Changes proposed in this merge request:
-
Ensure an empty string instance-name is handled correctly when generating ByteStream
resource-names.