Correct bug in abbr cause by missing " " separator (#19605)

Only 1 letter ABBR is generated after typing in a COMPANY NAME separated by spaces. This is due to missing " " value in split method.

For example: 

Company Name:    ABC Multiple Industries
Generates Abbr:     A
Correct Abbr should be:  AMI

This is caused by mission " " in split method.
diff --git a/erpnext/setup/doctype/company/company.js b/erpnext/setup/doctype/company/company.js
index 313de67..81c5f02 100644
--- a/erpnext/setup/doctype/company/company.js
+++ b/erpnext/setup/doctype/company/company.js
@@ -29,7 +29,8 @@
 
 	company_name: function(frm) {
 		if(frm.doc.__islocal) {
-			let parts = frm.doc.company_name.split();
+			# add missing " " arg in split method
+			let parts = frm.doc.company_name.split(" ");
 			let abbr = $.map(parts, function (p) {
 				return p? p.substr(0, 1) : null;
 			}).join("");