changed environment variable name for `minimum2scp:trigger` task
changed environment variable name for `minimum2scp:trigger` task

Use `_` instead of `-` as environent variable name,
For example, pass `ruby_full_TIRGGER_TOKEN` environment vairable
to run `rake minimum2scp:trigger[ruby-full]`.

mac-/dockerfiles,minimum2scp/dockerfiles,mac-/dockerfiles,minimum2scp/dockerfiles,minimum2scp/dockerfiles