DDL ignored by ddl job finishedTs less than puller resolvedTs

[sdojjy]

assume there are two ddl jobs
Job 60 : ALTER TABLE a ADD COLUMN x, y, z， it's commit ts is 400
Job 62: ALTER TABLE b ADD COLUMN y it's commit ts is 300

TiCDC sorts these jobs and run Job 62 first, then Job 60
DDL Puller processed Job 62 and set p.schemaVersion to 62,

tiflow/cdc/puller/ddl_puller.go

Line 483 in d728d02

p.schemaVersion = job.BinlogInfo.SchemaVersion

Job 60 will be ignored due to b.BinlogInfo.SchemaVersion <= p.schemaVersion

ddl job finishedTs less than puller resolvedTs,discard the ddl job

tiflow/cdc/puller/ddl_puller.go

Line 321 in d728d02

job.BinlogInfo.SchemaVersion <= p.schemaVersion {