fix: catch error properly for deleteall

[jannyHou]

Moved the description here:

When the SQL returnes a warning, there is a non-null err and the info is an empty array so info[o].affectedRows blows up

This PR is created to fix ^

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• [ ] npm test passes on your machine
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[agnes512]

I found other operations use cb(err, {count: Number.parseInt(info[0].affectedRows, 10)}); too. Maybe we can fix them as well?

[jannyHou]

@agnes512 Sure 👍 updated as well.