test: Mock to sqlite3

[asukaminato0721]

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Summary

#38159

Screenshots

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Checklist

• This change requires a documentation update, included: Dify Document
• I understand that this PR may be closed in case there was no previous discussion or issues. (This doesn't apply to typos!)
• I've added a test for each change that was introduced, and I tried as much as possible to make a single atomic change.
• I've updated the documentation accordingly.
• I ran make lint && make type-check (backend) and cd web && pnpm exec vp staged (frontend) to appease the lint gods

[github-actions]

Pyrefly Type Coverage

Metric	Base	PR	Delta
Type coverage	52.64%	52.77%	+0.13%
Strict coverage	52.16%	52.29%	+0.13%
Typed symbols	32,587	32,684	+97
Untyped symbols	29,585	29,523	-62
Modules	2982	2982	0

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