fix: [MSSQL] entries without prohibit_update also failed (#1065)

[#185149499]

We were passing default and required fields to the update
operation and some of these fields have prohibit update so
every entry was failing but not necessarily for the right
reason.

integration-tests/mssql_test.go

@@ -196,7 +196,7 @@ var _ = Describe("MSSQL", Label("MSSQL"), func() {
 
 		DescribeTable("should prevent updating properties flagged as `prohibit_update` because it can result in the recreation of the service instance",
 			func(prop string, value any) {
-				err := broker.Update(instanceID, msSQLServiceName, customMSSQLPlan["name"].(string), buildProperties(defaultProperties(), requiredProperties(), map[string]any{prop: value}))
+				err := broker.Update(instanceID, msSQLServiceName, customMSSQLPlan["name"].(string), map[string]any{prop: value})
 
 				Expect(err).To(MatchError(
 					ContainSubstring(