cherrypick: Added a new `PrepareBackup` RPC for snapshot backup (#1204)#1219

Merged

YuJuncen merged 1 commit intopingcap:release-6.5from YuJuncen:advanced-prepare-6.5

Jan 12, 2024

+1,045-248

Commits on Jan 11, 2024

Added a new PrepareBackup RPC for snapshot backup (pingcap#1204 )
YuJuncen
committed