python site-packages directory is missing in the installed directory

[QingleiCao]

Describe the bug

In parsec.env.sh in the installed bin directory, site-packages is provided to PYTHONPATH, but it is missing in the installed lib/lib64 directory.

To Reproduce

Steps to reproduce the behavior:

1. Checkout version 'commit-hash'
2. Compile with the following options '....' [e.g., head config.log]
3. Run test '....' [e.g. ctest --output-on-failure -R xyz]
4. See error

Expected behavior

A clear and concise description of what you expected to happen.

Environment (please complete the following information):

• PaRSEC version: [e.g., git hash]
• OS: [e.g. CentOS/7]
• Compiler: [e.g. GCC/7.3.0]
• MPI version: [e.g. Open MPI/4.1.2]

Additional context

Add any other context about the problem here. The content of the config.log file can be useful in some cases.