* Added s390x platform support
* Adapt to existing platform naming scheme
* Updated s390_64 library whitelist
* Use g++ compiler version 8.x for s390x
* Introduced dedicated Docker container for building s390x artifacts Minor fix
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Signed-off-by: Dirk Haubenreisser <haubenr@de.ibm.com>
Co-authored-by: Eric Anderson <ejona@google.com>