Run external servers with sys.executable -m (#6095)

This ensures that if the environment path is not correct, we should still be
able to resolve the granian, gunicorn, and uvicorn modules when executing the
server in a subprocess.

Author: masenf

reflex/utils/exec.py

@@ -612,6 +612,8 @@ def run_uvicorn_backend_prod(host: str, port: int, loglevel: LogLevel):
 
     if constants.IS_WINDOWS:
         command = [
+            sys.executable,
+            "-m",
             "uvicorn",
             *("--host", host),
             *("--port", str(port)),
@@ -627,6 +629,8 @@ def run_uvicorn_backend_prod(host: str, port: int, loglevel: LogLevel):
 
         # Our default args, then env args (env args win on conflicts)
         command = [
+            sys.executable,
+            "-m",
             "gunicorn",
             "--preload",
             *("--worker-class", "uvicorn.workers.UvicornH11Worker"),
@@ -663,6 +667,8 @@ def run_granian_backend_prod(host: str, port: int, loglevel: LogLevel):
     from reflex.utils import processes
 
     command = [
+        sys.executable,
+        "-m",
         "granian",
         *("--log-level", "critical"),
         *("--host", host),