Prevent artifactual "running from outside your current environment" e…

…rror (#15647)

Prevent warning when shutil.executable returns a symlink

Co-authored-by: Luca Antiga <luca@lightning.ai>
(cherry picked from commit 3248f33)

src/lightning_app/utilities/cli_helpers.py

@@ -299,10 +299,11 @@ def _check_environment_and_redirect():
     If not, this utility tries to redirect the ``lightning`` call to the environment executable (prompting the user to
     install lightning for them there if needed).
     """
-    env_executable = shutil.which("python")
+    env_executable = os.path.realpath(shutil.which("python"))
+    sys_executable = os.path.realpath(sys.executable)
 
     # on windows, the extension might be different, where one uses `.EXE` and the other `.exe`
-    if env_executable.lower() != sys.executable.lower():
+    if env_executable.lower() != sys_executable.lower():
         logger.info(
             "Lightning is running from outside your current environment. Switching to your current environment."
         )