bootstrap.py: Always use .exe for Windows

This ensure that it will run the Windows executable if other files in the directory (such as Linux executables) have the same file name minus the extension.

src/bootstrap/bootstrap.py

@@ -152,6 +152,10 @@ def run(args, verbose=False, exception=False, is_bootstrap=False, **kwargs):
     if verbose:
         print("running: " + ' '.join(args))
     sys.stdout.flush()
+    # Ensure that the .exe is used on Windoows just in case a Linux ELF has been
+    # compiled in the same directory.
+    if os.name == 'nt' and not args[0].endswith('.exe'):
+        args[0] += '.exe'
     # Use Popen here instead of call() as it apparently allows powershell on
     # Windows to not lock up waiting for input presumably.
     ret = subprocess.Popen(args, **kwargs)