test: disable shopping cart before running Tax Rule tests (#25183)

diff --git a/erpnext/accounts/doctype/tax_rule/test_tax_rule.py b/erpnext/accounts/doctype/tax_rule/test_tax_rule.py
index 632e30d..ac1ffd9 100644
--- a/erpnext/accounts/doctype/tax_rule/test_tax_rule.py
+++ b/erpnext/accounts/doctype/tax_rule/test_tax_rule.py
@@ -14,10 +14,15 @@
 from six import iteritems
 
 class TestTaxRule(unittest.TestCase):
-	def setUp(self):
+	@classmethod
+	def setUpClass(cls):
+		frappe.db.set_value("Shopping Cart Settings", None, "enabled", 0)
+
+	@classmethod
+	def tearDownClass(cls):
 		frappe.db.sql("delete from `tabTax Rule`")
 
-	def tearDown(self):
+	def setUp(self):
 		frappe.db.sql("delete from `tabTax Rule`")
 
 	def test_conflict(self):