OBSOLETED: This has been superseded by The debian-multiarch-triplet-provider-launch launcher: Enable DEBIAN_MULTIARCH_TRIPLET-like environment variable in the snap runtime - doc - snapcraft.io
This remote part provides a launcher that sets the SNAP_ARCH_TRIPLET environmental variable when it is not declared.
Refer the following forum topic for more info: GNU triplet via SNAP_ARCH_TRIPLET - snapd - snapcraft.io