Build for non-release versions is fails

[pablochacin]

#265 changed the way the kx6-disruptor go package version is set when building the custom k6 binary.

The logic now takes the package version passed to the build-package.sh command.

In the CI, this command receives the package version as defined in the build job, that for non-release versions (e.g. pr merge) the package version is set to devel-<commit>.

As a result, the build fails:

replace github.com/grafana/xk6-disruptor: version "dev-4434c64" invalid: unknown revision dev-4434c64