Do not checkout-downstream when no_pull is specified

Author: timfel

mx.graalpython/mx_graalpython.py

@@ -1864,7 +1864,8 @@ def update_import_cmd(args):
         join(overlaydir, "python", "graal", "ci"),
         dirs_exist_ok=True)
 
-    run_mx(['--dynamicimports', '/graal-enterprise', 'checkout-downstream', 'compiler', 'graal-enterprise'])
+    if not args.no_pull:
+        run_mx(['--dynamicimports', '/graal-enterprise', 'checkout-downstream', 'compiler', 'graal-enterprise'])
     enterprisedir = join(SUITE.dir, "..", "graal-enterprise")
     shutil.copy(
         join(enterprisedir, "common.json"),