There was a sleep statement in the test, waiting for Group
to perform a couple of evaluation. But looks like
it worked unreliable for some CI tests like the one below
https://github.com/VictoriaMetrics/VictoriaMetrics/actions/runs/8718213844/job/23915007958?pr=6115
This commit changes the sleep statement on a function that
waits for a specific number of evaluations. It should make this
test faster in general case, and more reliable for slow environemnts.
c9375cac5e
Descriptions were updated in attempt to make it more clear for readers,
re-phrasing and linking missing docs.
`eval_delay` was added to tests to verify it can be unmarshalled.
`eval_delay` is now applied before timestamp alignment to make it more predictable.
Before, if delay < interval the timestamp won't be aligned.
`eval_delay` and `eval_offset` was added to API output.
`PreviouslySentSeriesToRW` converted to private `previouslySentSeriesToRW`.
Signed-off-by: hagen1778 <roman@victoriametrics.com>
