process.env.profile is the string "undefined" instead of type undefined when no --profile is specified in the mode "run-multiple"

[mirao]

It's the same issue as #3339, but for the mode "run-multiple" only.
The bug causes that if you run codeceptjs run-multiple dev (without the option --profile), then process.env.profile is "undefined" instead of undefined
It may cause issues during further parsing of the variable. We hit the issue when trying to do something like env = process.env.profile; env = env || "dev"; which relies on undefined type value.

Details

• CodeceptJS version: 3.5.8