[BUG] Environment could not be retrieved if there is an incorrect PYTHONHOME env

Description
Environment could not be retrieved if there is an incorrect PYTHONHOME env

Setup
(Please provide relevant configs and/or SLS files (be sure to remove sensitive info. There is no general set-up of Salt.)

Please be as specific as possible and give set-up details.

• on-prem machine
• VM (Virtualbox, KVM, etc. please specify)
• VM running on a cloud service, please be explicit and add details
• container (Kubernetes, Docker, containerd, etc. please specify)
• or a combination, please be explicit
• jails if it is FreeBSD
• classic packaging
• onedir packaging
• used bootstrap to install

Steps to Reproduce the behavior
(Include debug logs if possible and relevant)

• Set incorrect PYTHONHOME env.

su testuser
cd ~
echo "export PYTHONHOME=/not/exist" > .profile

• Try cmd.run with runas. At this point, I confirmed that the results were different than expected.

salt 'mytest' cmd.run 'printenv' runas=testuser

• I could see the following error in the minion log.

2023-11-12 00:22:50,398 [salt.loaded.int.module.cmdmod:576 ][ERROR   ][136097] Environment could not be retrieved for user 'testuser': stderr="Python path configuration:\n  PYTHONHOME = '/not/exist'\n  PYTHONPATH = (not set)\n  program name = '/opt/saltstack/salt/bin/python3.10'\n  isolated = 0\n  environment = 1\n  user site = 1\n  import site = 1\n  sys._base_executable = '/opt/saltstack/salt/bin/python3.10'\n  sys.base_prefix = '/not/exist'\n  sys.base_exec_prefix = '/not/exist'\n  sys.platlibdir = 'lib'\n  sys.executable = '/opt/saltstack/salt/bin/python3.10'\n  sys.prefix = '/not/exist'\n  sys.exec_prefix = '/not/exist'\n  sys.path = [\n    '/not/exist/lib/python310.zip',\n    '/not/exist/lib/python3.10',\n    '/not/exist/lib/python3.10/lib-dynload',\n  ]\nFatal Python error: init_fs_encoding: failed to get the Python codec of the filesystem encoding\nPython runtime state: core initialized\nModuleNotFoundError: No module named 'encodings'\n\nCurrent thread 0x00007fd5d750e740 (most recent call first):\n  <no Python frame>\n" stdout=''

Expected behavior
The error "Environment could not have been saved for user" should not occur and should operate normally.

Screenshots
If applicable, add screenshots to help explain your problem.

Versions Report

Salt Version:
          Salt: 3006.2

Python Version:
        Python: 3.10.12 (main, Aug  3 2023, 21:47:10) [GCC 11.2.0]

Dependency Versions:
          cffi: 1.14.6
      cherrypy: unknown
      dateutil: 2.8.1
     docker-py: Not Installed
         gitdb: Not Installed
     gitpython: Not Installed
        Jinja2: 3.1.2
       libgit2: Not Installed
  looseversion: 1.0.2
      M2Crypto: Not Installed
          Mako: Not Installed
       msgpack: 1.0.2
  msgpack-pure: Not Installed
  mysql-python: Not Installed
     packaging: 22.0
     pycparser: 2.21
      pycrypto: Not Installed
  pycryptodome: 3.9.8
        pygit2: Not Installed
  python-gnupg: 0.4.8
        PyYAML: 6.0.1
         PyZMQ: 23.2.0
        relenv: 0.13.3
         smmap: Not Installed
       timelib: 0.2.4
       Tornado: 4.5.3
           ZMQ: 4.3.4

System Versions:
          dist: rhel 8.8 Ootpa
        locale: utf-8
       machine: x86_64
       release: 4.18.0-477.15.1.el8_8.x86_64
        system: Linux
       version: Red Hat Enterprise Linux 8.8 Ootpa

Additional context
PYTHONHOME seems to need an unset when running env_cmd.

Start by tracing the env_cmd path used by cmd.run with runas=testuser, focusing on how the user's environment is retrieved and how PYTHONHOME is passed. Reproduce the case with PYTHONHOME=/not/exist and verify that environment retrieval succeeds without the reported error.