[gcmole] Python conversion followup

Fix the python call to sys.executable, and sort imports

Change-Id: I948291e0835c79445108f215e55885fdb2c01052
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2560592
Commit-Queue: Michael Achenbach <machenbach@chromium.org>
Auto-Submit: Leszek Swirski <leszeks@chromium.org>
Reviewed-by: Michael Achenbach <machenbach@chromium.org>
Cr-Commit-Position: refs/heads/master@{#71423}

tools/gcmole/gcmole.py

@@ -9,13 +9,13 @@
 # for py2/py3 compatibility
 from __future__ import print_function
 
-import sys
+import collections
+import difflib
+import multiprocessing
 import os
 import re
-import difflib
 import subprocess
-import multiprocessing
-import collections
+import sys
 
 ArchCfg = collections.namedtuple("ArchCfg",
                                  ["triple", "arch_define", "arch_options"])

tools/gcmole/run-gcmole.py

@@ -26,7 +26,7 @@ if not os.path.isfile("out/build/gen/torque-generated/builtin-definitions.h"):
   sys.exit(-1)
 
 proc = subprocess.Popen(
-    ["python", DRIVER] + sys.argv[1:],
+    [sys.executable, DRIVER] + sys.argv[1:],
     env={'CLANG_BIN': CLANG_BIN, 'CLANG_PLUGINS': CLANG_PLUGINS},
     cwd=BASE_PATH,
 )