Parse each row of pg_stat_activity separately inside a try/catch

[sethsamuel]

What does this PR do?

Parses each row in pg_stat_activity individually.

Motivation

Azure databases are inserting invalid UTF8 into the pg_stat_activity table. To avoid crashing we need to parse each row individually and skip rows with invalid UTF8.

Additional Notes

Review checklist (to be filled by reviewers)

• Feature or bugfix MUST have appropriate tests (unit, integration, e2e)
• Changelog entries must be created for modifications to shipped code
• Add the qa/skip-qa label if the PR doesn't need to be tested during QA.
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