Strip `${PYTHON_VERSION}` from executables
Strip `${PYTHON_VERSION}` from executables

Now that the conda environment is being properly activated during Docker
`RUN` steps, there is no more needed to use the postfix version on
things like `conda` or `python`. Plus these might actually be messing up
`conda` operations in particular. So go ahead drop these to simplify
things.

DudLab/docker_nanshe_workflow,DudLab/docker_nanshe_workflow,nanshe-org/docker_nanshe_workflow,nanshe-org/docker_nanshe_workflow