Make GEM_EPHEM_NAME customizable via an env variable
Make GEM_EPHEM_NAME customizable via an env variable


Former-commit-id: b7d5f83ce3eaf00a1b766c701c10cee58b510e13 [formerly 3daa6f7f7f1073e3ba597adb30ad524e9c695f2b]
Former-commit-id: 3879a73cbb10e5ea89c311ecbce6b6d7e0eed269
gem/oq-engine,gem/oq-engine,gem/oq-engine,gem/oq-engine,gem/oq-engine