[new release] sqlite3 (5.3.1)
CHANGES:
- Made reference counting of database handles atomic for thread-safety. Thanks
to Christoph Wintersteiger for the suggestion, and to `o3-mini-high` for
finding a reference counting bug when handling exceptions.
- Fixed collation link freeing bug. Thanks to `o3-mini-high` for suggesting the
fix without even being prompted (minus-shot).
- Removed obsolete compiler flags. OCaml already passes optimization flags, and
flags for position-independent code should not be necessary. Thanks to Jonah
Beckford for the contribution.