Update tidb-lightning-tidb-backend.md (#2978)#2984

yikeke merged 1 commit into

pingcap:release-3.1pingcap/docs:release-3.1from

ti-srebot:release-3.1-9dba1aacf7e7ti-srebot/docs:release-3.1-9dba1aacf7e7Copy head branch name to clipboard