Fix for sqlalchemy 2 and text upgrades

[pjaol]

Description

Quick fix for task history logging and sqlalchemy 2.x

Motivation and Context

Using sqlalchemy 2.x breaks luigid if task history is enabled
e.g.

[task_history]
db_connection = sqlite:///./log/luigi-task-hist.sqlite

Results in luigid exiting

File ".../env/lib/python3.11/site-packages/luigi/db_task_history.py", line 271, in _upgrade_schema
    for i in conn.execute('PRAGMA table_info(task_parameters);').fetchall():
             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File ".../env/lib/python3.11/site-packages/sqlalchemy/engine/base.py", line 1414, in execute
    raise exc.ObjectNotExecutableError(statement) from err
sqlalchemy.exc.ObjectNotExecutableError: Not an executable object: 'PRAGMA table_info(task_parameters);'

This is because sqlalchemy requires a sqlalchemy.text object vs string in conn.execute

Have you tested this? If so, how?

Tested locally with sqlite3 and sqlalchemy 2.0.23 and luigi 3.4.0

[pjaol]

Hey @dlstadther what can I do to help move this forward?
I'm not sure what to look at to increase the code cov test

[metazool]

Just encountered this issue and was considering making a similar set of changes, glad I didn't!

Tried running the tests locally with tox as suggested in CONTRIBUTING.rst and there are some changes in tox 4 which would need reflecting here as well - the pass_env syntax changes as shown here, and tox -e py3X-core test/example.py etc needs a -- before non-tox options now

For now our project can pin an older version of sqlalchemy but it would be lovely to see this PR progress, does your user base have much to lose by dropping python 3.6 support in order to gain sqlalchemy 2.X? It's been end-of-life for a while...

[dlstadther]

Looking at https://pypistats.org/packages/luigi , there is virtually no 3.6 usage of luigi.
I'd be fine removing the support for 3.6, but would require a major version incremental of the project. So recent outstanding PRs would need to be merged and released first.

[dlstadther]

Looking back at past releases, we haven't performed a major version increment when dropping a specific minor version of python.

[dlstadther]

FYI. I've submitted #3325

[metazool]

FYI. I've submitted #3325

That's very reassuring to see, thank you