Python 3.13+ reports sqlite3 connections that are garbage collected
without being closed. The unit tests print a run of
"ResourceWarning: unclosed database" lines on Linux/CPython 3.14:
- SQLAlchemy.close() only returned its connection to the engine's
pool, so the underlying DBAPI connection (e.g. sqlite3 for
'-d sqlite://...') stayed open. Dispose the engine on close.
- vulnTest() used "with sqlite3.connect(...)", which commits but does
not close the connection. Use contextlib.closing().
- test_multibit and test_sqlalchemy never closed what they opened.
Co-authored-by: PiyushSatyarthi <244159432+PiyushSatyarthi@users.noreply.github.com>
