tsdb: fix sequence check for WAL segments (#7032)
tsdb: fix sequence check for WAL segments (#7032)

Signed-off-by: zhulongcheng <2fa797c4ec90e744aa9187d34843a67aa80e4e9d@gmail.com>
GoogleCloudPlatform/prometheus,Gouthamve/prometheus,alileza/prometheus,prometheus/prometheus,keegancsmith/prometheus,prometheus/prometheus,kangwoo/prometheus,GoogleCloudPlatform/prometheus,kangwoo/prometheus,GoogleCloudPlatform/prometheus,kangwoo/prometheus,alileza/prometheus,alileza/prometheus,keegancsmith/prometheus,keegancsmith/prometheus,prometheus/prometheus,GoogleCloudPlatform/prometheus,Gouthamve/prometheus,prometheus/prometheus,kangwoo/prometheus,alileza/prometheus,Gouthamve/prometheus,Gouthamve/prometheus,keegancsmith/prometheus,prometheus/prometheus,alileza/prometheus,GoogleCloudPlatform/prometheus,keegancsmith/prometheus