macros-core: give SQLX_OFFLINE_DIR from environment precedence (#3962) #1426

Job	Run time
Check	1m 41s
Integration Test (ubuntu-latest)	39s
Integration Test (macOS-13)	1m 12s
Integration Test (macOS-latest)	1m 3s
Functional Test (PostgreSQL)	48s
Functional Test (MySQL)	50s
Functional Test (SQLite)	37s
Build (ubuntu-latest)	2m 53s
Build (macOS-13)	3m 41s
Build (windows-latest)	5m 38s
Build (macOS-latest)	1m 47s
	20m 49s

Provide feedback