[postgres] Emit raw query statements and plans for non prepared statements

[lu-zhengda]

What does this PR do?

This PR introduces a feature to ingest raw query statements and explain plans when the collect_raw_query_statement.enabled option is set to true. The raw query statement is collected alongside activity samples, which contains the query statement text before obfuscation and normalization.

Motivation

https://datadoghq.atlassian.net/browse/DBMON-4956

Review checklist (to be filled by reviewers)

• Feature or bugfix MUST have appropriate tests (unit, integration, e2e)
• Add the qa/skip-qa label if the PR doesn't need to be tested during QA.
• If you need to backport this PR to another branch, you can add the backport/<branch-name> label to the PR and it will automatically open a backport PR once this one is merged

[codecov]

Codecov Report

Attention: Patch coverage is 92.59259% with 8 lines in your changes missing coverage. Please review.

Project coverage is 86.83%. Comparing base (ba11c25) to head (d5173e3).
Report is 6 commits behind head on master.

Additional details and impacted files

Flag	Coverage Δ
activemq	?
cassandra	?
hive	?
hivemq	?
hudi	?
ignite	?
jboss_wildfly	?
kafka	?
postgres	93.27% <92.59%> (?)
presto	?
solr	?

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