python: Apply Black formatter to Python files

The command executed was `black src configs tests util`.

Change-Id: I8dfaa6ab04658fea37618127d6ac19270028d771
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/47024
Maintainer: Bobby Bruce <bbruce@ucdavis.edu>
Reviewed-by: Jason Lowe-Power <power.jg@gmail.com>
Reviewed-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Tested-by: kokoro <noreply+kokoro@google.com>

src/python/m5/internal/params.py

@@ -40,5 +40,5 @@ import inspect
 import _m5
 
 for name, module in inspect.getmembers(_m5):
-    if name.startswith('param_') or name.startswith('enum_'):
+    if name.startswith("param_") or name.startswith("enum_"):
         exec("from _m5.%s import *" % name)