feat: replace CLS with ALS, enable ALS by default, discourage unmanaged transactions

[ephys]

Pull Request Checklist

• Have you added new tests to prevent regressions?
• If a documentation update is necessary, have you opened a PR to the documentation repository?
• Did you update the typescript typings accordingly (if applicable)?
• Does the description below contain a link to an existing issue (Closes #[issue]) or a description of the issue you are solving?
• Does the name of your PR follow our conventions?

Description Of Change

Closes #15291
Closes #13742

This PR drops CLS in favor of using node's built-in AsyncLocalStorage.

The AsyncLocalStorage is now per Sequelize instance instead of global. It never made sense for this option to be global.

It also enables ALS transactions by default. They can be disabled by setting disableAlsTransactions to true in Sequelize's options.

Finally, in order to discourage using unmanaged transactions (which are easy to misuse), this PR removes the ability to get an unmanaged transaction by not providing a callback to sequelize.transaction().
Unmanaged transactions are now started using sequelize.startUnmanagedTransaction() instead.

Todos

• Open a PR to update the documentation website

[WikiRik]

Looks good! Don't forget to remove cls-hooked from package.json, apart from that it's just a few typos

[fzn0x]

This is interesting

[WikiRik]

I found a last reference to CLS here;

sequelize/test/unit/dialects/abstract/query.test.js

Line 478 in a2df979

describe('_logQuery', () => {

But we should be good after that

[ephys]

I don't know why that's called CLS but it doesn't seem to be related to Continuation local storage

[WikiRik]

Maybe rename it to customQuery?

[WikiRik]

We can do the rename in a different PR

[ephys]

Yes let's leave it as is, we'll update the test suite when we migrate it and/or query.js to TypeScript

[OmriSama]

The v7 alpha documentation still mentions cls-hooked; is it going to be updated?

[ephys]

It is, the update is in sequelize/website#419, which I need to update & get merged