In one of my client website, I found this error on backend. When I investigated on google there were some answers but those answers were not working with this version.
then I personally checked the issues.
so the problem is
gravityforms/assets/js/dist/vendor-admin.min.js these dist js are loading before
var gform; is undefined for those first enqueued js files and then all these errors starts.
why this happenening?
I checked the code and found that
wp_register_script( 'gform_gravityforms_admin_vendors' this registration should have
'gform_gravityforms' as dependency. Currently there is no dependency on that registration of script.
I hope Gravity form team will test this solution and apply a good fix in future versions.