Implement 'From<Option>' for 'MaybeUnset'

[stanislav-tkach]

I think it is convenient to simplify conversion from Option<T> to MaybeUnset<T>, but maybe I'm missing something.

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[wprzytula]

❓ Did you consider that Option::None already represents presence of the CQL null value, which is different from absence of value that MaybeUnset represents?

[github-actions]

cargo semver-checks found no API-breaking changes in this PR! 🎉🥳
Checked commit: df112a0

[stanislav-tkach]

@wprzytula
I see, but From conversion is explicit, so I still consider it useful. But feel free to close the pull request if you think it will create confusion.

[wprzytula]

@wprzytula I see, but From conversion is explicit, so I still consider it useful. But feel free to close the pull request if you think it will create confusion.

I'm in two minds. @Lorak-mmk @muzarski WDYT?

[Lorak-mmk]

I'm against such conversions. It doesn't save a lot of typing, but it may introduce unwanted behavior.

[stanislav-tkach]

Ok, no problem.