Fixed overlooked hardcoded venv name.

templates/build_python_environment.sh

@@ -40,7 +40,7 @@ spack load python@3.8:
 
 PYTHON_ENVIRONMENT_FOLDER=%python_environment.folder_name%
 
-if [ ! -d venv ]; then
+if [ ! -d ${PYTHON_ENVIRONMENT_FOLDER} ]; then
   # Create virtual environment
   python3 -m venv --prompt AS ${PYTHON_ENVIRONMENT_FOLDER}
 fi