chore: Fix warnings for custom postgres_## cfg flags #1434

Job	Run time
Integration Test (macOS-latest)	58s
Integration Test (macOS-13)	1m 9s
Check	1m 30s
Build (windows-latest)	1m 46s
Functional Test (MySQL)	58s
Build (ubuntu-latest)	47s
Build (macOS-13)	1m 12s
Integration Test (ubuntu-latest)	36s
Build (macOS-latest)	40s
Functional Test (SQLite)	39s
Functional Test (PostgreSQL)	49s
	11m 4s

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