Split migrations folder (#21549)

There are too many files in `models/migrations` folder so that I split
them into sub folders.

models/migrations/v1_17/v222.go

@@ -0,0 +1,65 @@
+// Copyright 2022 The Gitea Authors. All rights reserved.
+// Use of this source code is governed by a MIT-style
+// license that can be found in the LICENSE file.
+
+package v1_17 // nolint
+
+import (
+	"context"
+	"fmt"
+
+	"code.gitea.io/gitea/models/migrations/base"
+	"code.gitea.io/gitea/modules/timeutil"
+
+	"xorm.io/xorm"
+)
+
+func DropOldCredentialIDColumn(x *xorm.Engine) error {
+	// This migration maybe rerun so that we should check if it has been run
+	credentialIDExist, err := x.Dialect().IsColumnExist(x.DB(), context.Background(), "webauthn_credential", "credential_id")
+	if err != nil {
+		return err
+	}
+	if !credentialIDExist {
+		// Column is already non-extant
+		return nil
+	}
+	credentialIDBytesExists, err := x.Dialect().IsColumnExist(x.DB(), context.Background(), "webauthn_credential", "credential_id_bytes")
+	if err != nil {
+		return err
+	}
+	if !credentialIDBytesExists {
+		// looks like 221 hasn't properly run
+		return fmt.Errorf("webauthn_credential does not have a credential_id_bytes column... it is not safe to run this migration")
+	}
+
+	// Create webauthnCredential table
+	type webauthnCredential struct {
+		ID           int64 `xorm:"pk autoincr"`
+		Name         string
+		LowerName    string `xorm:"unique(s)"`
+		UserID       int64  `xorm:"INDEX unique(s)"`
+		CredentialID string `xorm:"INDEX VARCHAR(410)"`
+		// Note the lack of the INDEX on CredentialIDBytes - we will add this in v223.go
+		CredentialIDBytes []byte `xorm:"VARBINARY(1024)"` // CredentialID is at most 1023 bytes as per spec released 20 July 2022
+		PublicKey         []byte
+		AttestationType   string
+		AAGUID            []byte
+		SignCount         uint32 `xorm:"BIGINT"`
+		CloneWarning      bool
+		CreatedUnix       timeutil.TimeStamp `xorm:"INDEX created"`
+		UpdatedUnix       timeutil.TimeStamp `xorm:"INDEX updated"`
+	}
+	if err := x.Sync2(&webauthnCredential{}); err != nil {
+		return err
+	}
+
+	// Drop the old credential ID
+	sess := x.NewSession()
+	defer sess.Close()
+
+	if err := base.DropTableColumns(sess, "webauthn_credential", "credential_id"); err != nil {
+		return fmt.Errorf("unable to drop old credentialID column: %w", err)
+	}
+	return sess.Commit()
+}