translate: make test generic [(#3386)](https://github.com/GoogleCloudPlatform/python-docs-samples/issues/3386)
translate: make test generic [(#3386)](https://github.com/GoogleCloudPlatform/python-docs-samples/issues/3386)

Fix: https://github.com/GoogleCloudPlatform/python-docs-samples/issues/3381
googleapis/python-translate,googleapis/python-translate