nixos/test-driver: use ipython via ptpython

Closes #180089

I realized that the previous commits relying on `sys.exit` for dealing
with `MachineError`/`RequestedAssertionFailed` exit the interactive
session which is kinda bad.

This patch uses the ipython driver: it seems to have equivalent features
such as auto-completion and doesn't stop on SystemExit being raised.

This also fixes other places where this happened such as things calling
`log.error` on the CompositeLogger.

nixos/lib/test-driver/default.nix

@@ -31,6 +31,7 @@ python3Packages.buildPythonApplication {
       colorama
       junit-xml
       ptpython
+      ipython
     ]
     ++ extraPythonPackages python3Packages;
 

nixos/lib/test-driver/src/test_driver/__init__.py

@@ -3,7 +3,7 @@ import os
 import time
 from pathlib import Path
 
-import ptpython.repl
+import ptpython.ipython
 
 from test_driver.driver import Driver
 from test_driver.logger import (
@@ -136,11 +136,10 @@ def main() -> None:
         if args.interactive:
             history_dir = os.getcwd()
             history_path = os.path.join(history_dir, ".nixos-test-history")
-            ptpython.repl.embed(
-                driver.test_symbols(),
-                {},
+            ptpython.ipython.embed(
+                user_ns=driver.test_symbols(),
                 history_filename=history_path,
-            )
+            )  # type:ignore
         else:
             tic = time.time()
             driver.run_tests()