Revert "Remove unnecessary notify=None from git cl upload."

This reverts commit 7688e784503525b598a18991e190038381c333cf.

Reason for revert: afaict there is a gerrit notifications bug b/297928626 unrelated to this change but i'm reverting this anyway and relanding when the gerrit bug is resolved.

Original change's description:
> Remove unnecessary notify=None from git cl upload.
>
> This is a NOOP change for all cases except for "Publish comments on push" which gets fixed with this CL.
> Our hosts have the notify on each patchset turned off.
>
> Bug: 1472724
> Change-Id: I3672c383b1e4ca1f6243c9b9d2c906473f5037d9
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/tools/depot_tools/+/4797981
> Reviewed-by: Gavin Mak <gavinmak@google.com>
> Commit-Queue: Joanna Wang <jojwang@chromium.org>

Bug: 1472724
Change-Id: I3de1a25fe84a21a2adb8b4bbddb460dd45530418
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/tools/depot_tools/+/4817767
Reviewed-by: Gavin Mak <gavinmak@google.com>
Commit-Queue: Joanna Wang <jojwang@chromium.org>
diff --git a/git_cl.py b/git_cl.py
index 95a70f3..00bedb4 100755
--- a/git_cl.py
+++ b/git_cl.py
@@ -1571,6 +1571,8 @@
       refspec_opts.append('notify=ALL')
     elif (not self.GetIssue() and options.squash and not dogfood_path):
       refspec_opts.append('wip')
+    else:
+      refspec_opts.append('notify=NONE')
 
     # TODO(tandrii): options.message should be posted as a comment if
     # --send-mail or --send-email is set on non-initial upload as Rietveld used