perf: don't track seen for POS Invoice (backport #46187) (#46188)

* perf: don't track seen for POS Invoice (#46187)

This is a moving doctype. Do people even browse the list view?

It doesn't make much sense, either. POS INvoices are rarely "reviewed" by multiple users.

(cherry picked from commit ded0aab680)

# Conflicts:
#	erpnext/accounts/doctype/pos_invoice/pos_invoice.json

* chore: conflicts

---------

Co-authored-by: Ankush Menat <ankush@frappe.io>

erpnext/accounts/doctype/pos_invoice/pos_invoice.json

@@ -1623,6 +1623,5 @@
  "states": [],
  "timeline_field": "customer",
  "title_field": "title",
- "track_changes": 1,
+ "track_changes": 1
- "track_seen": 1
+}
-}