Only try to JSON-ify job metadata and file metadata if not None in the FTS client

1 job for develop in 28 seconds (queued for 1 second)
Status Job ID Name Coverage
failed build #11718938


Name Stage Failure
build Build
Public key for libtommath-0.42.0-6.el7.x86_64.rpm is not installed

Error downloading packages:
gfal2-2.19.0-r2101141321.el7.x86_64: [Errno 256] No more mirrors to try.

time="2021-01-20T14:36:46Z" level=fatal msg="The command '/bin/sh -c /usr/bin/yum install -y fts-rest-selinux fts-rest httpd MySQL-python' returned a non-zero code: 1"
Cleaning up file based variables
ERROR: Job failed: exit code 1