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• Does npm run test or npm run test-DIALECT pass with this change (including linting)?
• Does the description below contain a link to an existing issue (Closes #[issue]) or a description of the issue you are solving?
• Have you added new tests to prevent regressions?
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Description of change

I'm adding way to add index hints to a select query.

Example usage:

db.User.findOne({
    where: {
        email: 'joe@example.com',
    },
    indexHint: 'idx_name',
});

// This generates SELECT * FROM `User` USE INDEX (idx_name) WHERE ...

Here's an issue from a while ago requesting this feature. #6370
It went stale and was closed though.

(This is my first PR to open source/on github. I couldn't figure out how to get permissions to make a feature branch so I created a fork instead. If this is not desired I can change it.)