Incremental cache metrics
Currently, we calculate cache metrics in a job that runs every X minutes but this one queries the full cache collection every time leading to mongo query targeting issues in Mongo Atlas (ratio > 1000).
 
Alert message:
`The ratio of documents scanned to returned exceeded 1000.0 on  datasets-server-prod-shard-00-00.ujrd0.mongodb.net, which typically suggests that un-indexed queries are being run. 
`

In order to avoid this alert, this PR moves the metrics increase to simple_cache so that, every time a cache is recorded, it will update the metrics collection as well.

Note.- Job metrics will be added in another PR
Incremental cache metrics: Currently, we calculate cache metrics in a job that runs every X minutes but this one queries the full cache collection every time leading to mongo query targeting issues in Mongo Atlas (ratio > 1000).
 
Alert message:
`The ratio of documents scanned to returned exceeded 1000.0 on  datasets-server-prod-shard-00-00.ujrd0.mongodb.net, which typically suggests that un-indexed queries are being run. 
`

In order to avoid this alert, this PR moves the metrics increase to simple_cache so that, every time a cache is recorded, it will update the metrics collection as well.

Note.- Job metrics will be added in another PR