pex: rely on system site-packages for RPM packages installed - no manual editing of lockfile

[AlexTereshenkov]

23:24:38.61 [INFO] Canceled: Building 9 requirements for requirements.pex from the requirements/requirements.lock resolve: click, loguru, packaging, python-dateutil, python3-tabulate, requests, types-python-dateutil, types-reques... (21 characters truncated)
23:24:39.41 [INFO] Completed: Building 9 requirements for requirements.pex from the requirements/requirements.lock resolve: click, loguru, packaging, python-dateutil, python3-tabulate, requests, types-python-dateutil, types-reques... (21 characters truncated)
23:24:39.42 [ERROR] 1 Exception encountered:

Engine traceback:
  in `test` goal

ProcessExecutionFailure: Process 'Building 9 requirements for requirements.pex from the requirements/requirements.lock resolve: click, loguru, packaging, python-dateutil, python3-tabulate, requests, types-python-dateutil, types-requests, typing-extensions' failed with exit code 1.
stdout:

stderr:
Failed to resolve compatible artifacts from lock requirements/requirements.lock for 1 target:
1. /usr/bin/python3.9:
    Failed to resolve all requirements for cp39-cp39-manylinux_2_36_x86_64 interpreter at /usr/bin/python3.9 from requirements/requirements.lock:

Configured with:
    build: True
    use_wheel: True

Dependency on python3-tabulate (via: python3-tabulate) not satisfied, no candidates found.