Description of problem:
centos8.4迁移到anolis8.9时，出现如下错误
Make the repo status same before and after migrations...
No matching repo base in current system
No matching repo centosplus in current system
process pkgs for c7
Switch successful. Syncing with Anolis OS repositories.
Distro sync
AnolisOS-8 - AppStream                                                                                                                                                            0.0  B/s |   0  B     02:00    
Errors during downloading metadata for repository 'AppStream':
  - Curl error (28): Timeout was reached for http://mirrors.cloud.aliyuncs.com/anolis/8/AppStream/x86_64/os/repodata/repomd.xml [Connection timed out after 30001 milliseconds]
Error: Failed to download metadata for repo 'AppStream': Cannot download repomd.xml: Cannot download repodata/repomd.xml: All mirrors were tried

简单的分析了一下，是由于生成的repo中baseurl地址不可访问造成的。比如,AnolisOS-BaseOS.repo的内容如下：
[root@localhost yum.repos.d]# cat /etc/yum.repos.d/AnolisOS-BaseOS.repo 
[BaseOS]
name=AnolisOS-$releasever - BaseOS
baseurl=http://mirrors.cloud.aliyuncs.com/anolis/$releasever/BaseOS/$basearch/os
enabled=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-ANOLIS
gpgcheck=1

在执行升级前，我的机器上配置aliyun的repo源：
https://mirrors.aliyun.com/repo/Centos-vault-8.5.2111.repo

Version-Release number of selected component (if applicable):
CentOS Linux release 8.4.2105

How reproducible:


Steps to Reproduce:
1.配置https://mirrors.aliyun.com/repo/Centos-vault-8.5.2111.repo到本地
2.执行centos2anolis

Actual results:
迁移报错

Expected results:
迁移正常

Additional info: