Remove low level ingester client settings

[pracucci]

What this PR does:
We have 3 low level settings which we don't set in our jsonnet. I propose to just get rid of them and keep using the hardcoded defaults:

• -ingester-client.expected-labels
• -ingester-client.expected-samples-per-series
• -ingester-client.expected-timeseries

Which issue(s) this PR fixes:
N/A

Checklist

• Tests updated
• Documentation added
• CHANGELOG.md updated - the order of entries should be [CHANGE], [FEATURE], [ENHANCEMENT], [BUGFIX]

[pstibrany]

Sounds good.

[bboreham]

Arguably expectedTimeseries should equal the Prometheus default of 500.
I don’t think it matters much since the allocations are reused in a pool so the pool will tend to hold the biggest size used.

[pracucci]

Arguably expectedTimeseries should equal the Prometheus default of 500.
I don’t think it matters much since the allocations are reused in a pool so the pool will tend to hold the biggest size used.

👍 Tracked in a issue: #1154 (I prefer to keep this PR about CLI flag removal)