[receiver/hostmetrics] Unify feature gates for direction removal

[dmitryax]

This change replaces set of independent feature gates for transition from the metrics with direction attribute with two unified feature gates that are applied on all the metrics reported by the hostmetrics receiver.

• receiver.hostmetricsreceiver.emitMetricsWithDirectionAttribute
• receiver.hostmetricsreceiver.emitMetricsWithoutDirectionAttribute

Also this introduces the following changes to the transition process:

1. I shifts the transition schedule one release forward since disc scraper is not yet ready to emit the new metrics
2. It removes the warnings. They will be introduced in 0.56.0 when all the scrapers are aligned with the schedule.
3. It introduces an option to emit both the deprecated and the new metrics. This can be useful for users during the transition period.

Link to tracking Issue: #11815

[dmitryax]

Added "Skip Changelog" to pass CI until #12106 is merged

[dmitryax]

@codeboten PTAL and let me know what do you think. I would like to include it in the 0.55.0 release, feel free to remove the blocker label if you disagree

[tigrannajaryan]

@open-telemetry/collector-contrib-approvers please review/merge or remove the release:blocker label.

[mx-psi]

This looks good to me, but would prefer if @codeboten had a look too if he has more context

[codeboten]

Just one question and a comment, this consolidation makes sense to me. However it might be worth capturing here that it wont apply to the disk scraper just yet as that change hasn't been implemented.

[tigrannajaryan]

Test failed: https://github.com/open-telemetry/opentelemetry-collector-contrib/runs/7218945997?check_suite_focus=true

[dmitryax]

Test failed: https://github.com/open-telemetry/opentelemetry-collector-contrib/runs/7218945997?check_suite_focus=true

This seems to be a flaky unrelated prometheus receiver test, submitted #12126

[tigrannajaryan]

Please merge once the build passes. I will wait for it and will start the contrib release procedure.

[dmitryax]

@tigrannajaryan, merged