Fix manifest reference push for v2.1 to use JSON
Fix manifest reference push for v2.1 to use JSON

Signed-off-by: Phil Estes <dbac1f450dc8326caa7ba104b384a0eca642250c@gmail.com>

estesp/manifest-tool,estesp/manifest-tool,mathewkoshy493/manifest-tool,mathewkoshy493/manifest-tool