using an environment variable as the current_version

[OdedRub]

Hi, I'm trying for some time now to make the incremental versioning automatic by passing the previous version to the plugin as the current_version, but it keeps giving the error "previous version '$ENV' is not a semantic version. I made sure that the value of environment variable (ENV) is actually a valid semantic version (1.0.6) by printing it in different steps. Is there anything I need to know regarding this issue?