drift_flutter: Allow custom temporary directory #3091

Job	Run time
setup / Get and cache Dart dependencies	29s
setup / Compile sqlite3 for tests (ubuntu-latest)	5s
setup / Compile sqlite3 for tests (macos-latest)	10s
setup / Compile sqlite3 for tests (windows-latest)	11s
Documentation	4m 27s
sqlparser	44s
drift package	2m 10s
drift_dev	6m 23s
Integration tests for migration tooling	1m 6s
Integration tests	2m 43s
test_flutter (3.24)	2m 5s
test_flutter (3.27)	1m 57s
drift_web_ddc	3m 30s
Web integration tests	3m 54s
Drift web unit tests, dart2wasm, chrome	3m 29s
Drift web unit tests, dart2wasm, firefox	4m 13s
	37m 36s

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