Upgrade xorm to v0.8.0 (#8536)

vendor/xorm.io/xorm/statement_quote.go

@@ -0,0 +1,19 @@
+// Copyright 2019 The Xorm Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package xorm
+
+func trimQuote(s string) string {
+	if len(s) == 0 {
+		return s
+	}
+
+	if s[0] == '`' {
+		s = s[1:]
+	}
+	if len(s) > 0 && s[len(s)-1] == '`' {
+		return s[:len(s)-1]
+	}
+	return s
+}