Hints manager sent annotation, uses the wrong metric

[ViperRu]

scylla-monitoring/grafana/types.json

Line 4462 in f25d76d

"expr":"changes(scylla_hints_manager_written{cluster=\"$cluster\"}[$__rate_interval])>0",

Please correct to "scylla_hints_manager_sent"

[mykaul]

But those seem to be two different metrics:
https://github.com/scylladb/scylladb/blob/8550a38a8baab074a1b1b5f66ad321c9c5d669d9/db/hints/manager.cc#L151
https://github.com/scylladb/scylladb/blob/8550a38a8baab074a1b1b5f66ad321c9c5d669d9/db/hints/manager.cc#L160

[ViperRu]

But those seem to be two different metrics: https://github.com/scylladb/scylladb/blob/8550a38a8baab074a1b1b5f66ad321c9c5d669d9/db/hints/manager.cc#L151 https://github.com/scylladb/scylladb/blob/8550a38a8baab074a1b1b5f66ad321c9c5d669d9/db/hints/manager.cc#L160

Just now scylla_hints_manager_written is used both for the annotation_hints_sent and for the annotation_hints_writes.