Sqlean.py

No functional changes. Fixed `utf8_lookup` global symbol to facilitate [sqlean.go](https://github.com/riyaz-ali/sqlean.go) (#92).

Huge thanks to riyaz-ali for porting `sqlean` to Go!

No functional changes. Recompiled Linux extensions on Ubuntu 20.04 instead of 22.04 to fix 90.

Python 3.12 build (courtesy of edgarrmondragon). No other changes.

Allow setting `pragma` without transaction:

python
import sqlean
conn = sqlean.connect("/tmp/t1.db")
conn.execute("pragma journal_mode=wal;")


See https://github.com/coleifer/pysqlite3/issues/58 for details.

**Breaking**: all extensions are disabled by default. You can still use `sqlean` as a drop-in replacement for `sqlite3`. To enable all extensions, call `sqlean.extensions.enable_all()` before calling `connect()`:

python
import sqlean

sqlean.extensions.enable_all()

conn = sqlean.connect(":memory:")
cur = conn.execute("select median(value) from generate_series(1, 99)")
print(cur.fetchone())
conn.close()


To enable specific extensions, call `sqlean.extensions.enable()`:

python
import sqlean

sqlean.extensions.enable("stats", "text")
...


Versions: `sqlite` [3.42.0](https://sqlite.org/releaselog/3_42_0.html) + `sqlean` [0.21.5](https://github.com/nalgeon/sqlean/releases/0.21.5).

sqlite` [3.42.0](https://sqlite.org/releaselog/3_42_0.html) + `sqlean` [0.21.5](https://github.com/nalgeon/sqlean/releases/0.21.5).