Add missing postgres metrics

[wantsui]

Motivation

Changes

Brings the following postgres metrics building off https://github.com/DataDog/system-tests/pull/5752/files:

1. rollbacks
2. vacuums
3. blocks_read
4. index scans
5. commented out metrics

Workflow

1. ⚠️ Create your PR as draft ⚠️
2. Work on you PR until the CI passes
3. Mark it as ready for review
   • Test logic is modified? -> Get a review from RFC owner.
   • Framework is modified, or non obvious usage of it -> get a review from R&P team

🚀 Once your PR is reviewed and the CI green, you can merge it!

🛟 #apm-shared-testing 🛟

Reviewer checklist

• If PR title starts with [<language>], double-check that only <language> is impacted by the change
• No system-tests internal is modified. Otherwise, I have the approval from R&P team
• A docker base image is modified?
  • the relevant build-XXX-image label is present
• A scenario is added (or removed)?
  • Get a review from R&P team

[github-actions]

CODEOWNERS have been resolved as:

utils/otel_validators/validator_metrics.py                              @DataDog/system-tests-core
tests/otel_postgres_metrics_e2e/test_postgres_metrics.py                @DataDog/system-tests-core
utils/_context/containers.py                                            @DataDog/system-tests-core
utils/build/docker/otelcol-config-with-postgres.yaml                    @DataDog/system-tests-core
utils/otel_validators/__init__.py                                       @DataDog/system-tests-core

[quinna-h]

LGTM; the CI failure is expected because this otel collector image version is not compatible with some of the metrics. This test failure is accurate and should be captured by our testing pipeline.

This PR should fix the issues seen: update otel collector image version

[quinna-h]

Update: looks like updating the collector image version has fixed the previously failing jobs in CI