hold on to batch job stats till cleanup (#20480)

This PR also fixes job stats not available after restart

cmd/common-main.go

@@ -91,9 +91,6 @@ func init() {
 	logger.Init(GOPATH, GOROOT)
 	logger.RegisterError(config.FmtError)
 
-	globalBatchJobsMetrics = batchJobMetrics{metrics: make(map[string]*batchJobInfo)}
-	go globalBatchJobsMetrics.purgeJobMetrics()
-
 	t, _ := minioVersionToReleaseTime(Version)
 	if !t.IsZero() {
 		globalVersionUnix = uint64(t.Unix())