Fix git cl upload on Windows

Use ISO8601 time format standard to avoid localized result and need to
encode.

R=ehmaldonado@chromium.org

Bug: 1074002
Change-Id: I95c2ddd55a9661351f2b45601f7bba24c2951c31
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/tools/depot_tools/+/2163401
Reviewed-by: Edward Lesmes <ehmaldonado@chromium.org>
Commit-Queue: Josip Sokcevic <sokcevic@google.com>
diff --git a/tests/git_cl_test.py b/tests/git_cl_test.py
index 0ddc5a9..29c88d5 100755
--- a/tests/git_cl_test.py
+++ b/tests/git_cl_test.py
@@ -858,9 +858,6 @@
 
     final_description = final_description or post_amend_description.strip()
 
-    date_format = ('03/16/17 20:00:41'
-                   if sys.platform == 'win32' and sys.version_info.major == 2
-                   else 'Thu Mar 16 20:00:41 2017')
     trace_name = os.path.join('TRACES_DIR', '20170316T200041.000000')
 
     # Trace-related calls
@@ -877,7 +874,7 @@
                 '1000\n'
                 '0\n'
                 '%(trace_name)s' % {
-                    'date': date_format,
+                    'date': '2017-03-16T20:00:41.000000',
                     'short_hostname': short_hostname,
                     'change_id': change_id,
                     'description': final_description,