Easy to end up with &_save-slug= junk in the URL

[simonw]

I found myself on this page while using the dashboard:

https://simonwillison.net/dashboard/?sql=select+count%28%2A%29+from+blog_tag%3AKp4rETtwpkM90V3sDIVwjSeEWOtwhOXAA-l_oT0xCKg&sql=select+%2A+from+blog_tag+limit+10%3AFtD-wu_Rt3K3EjvwabfkFj-_X3cF3kWdsNSMktP08oc&_save-title=&_save-slug=&_save-description=&_save-view_policy=private&_save-view_group=&_save-edit_policy=private&_save-edit_group=

That &_save-title=&_save-slug=&_save-description=&_save-view_policy=private&_save-view_group=&_save-edit_policy=private&_save-edit_group= is unused cruft and shouldn't be there.