check if Data Migration Plan exists before deleting (#15368)

diff --git a/erpnext/patches/v10_0/delete_hub_documents.py b/erpnext/patches/v10_0/delete_hub_documents.py
index 293969b..0d81bd5 100644
--- a/erpnext/patches/v10_0/delete_hub_documents.py
+++ b/erpnext/patches/v10_0/delete_hub_documents.py
@@ -6,12 +6,12 @@
 	for dt, dn in (("Page", "Hub"), ("DocType", "Hub Settings"), ("DocType", "Hub Category")):
 		frappe.delete_doc(dt, dn, ignore_missing=True)
 
-	data_migration_plans = frappe.get_all("Data Migration Plan", filters={"module": 'Hub Node'})
-	for plan in data_migration_plans:
-		plan_doc = frappe.get_doc("Data Migration Plan", plan.name)
-		for m in plan_doc.get("mappings"):
-			frappe.delete_doc("Data Migration Mapping", m.mapping, force=True)
-		frappe.delete_doc("Data Migration Plan", plan.name)
+	if frappe.db.exists("DocType", "Data Migration Plan"):
+		data_migration_plans = frappe.get_all("Data Migration Plan", filters={"module": 'Hub Node'})
+		for plan in data_migration_plans:
+			plan_doc = frappe.get_doc("Data Migration Plan", plan.name)
+			for m in plan_doc.get("mappings"):
+				frappe.delete_doc("Data Migration Mapping", m.mapping, force=True)
+			frappe.delete_doc("Data Migration Plan", plan.name)
 
 	frappe.delete_doc("Module Def", "Hub Node", ignore_missing=True)
-	
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