Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

#187)

* feat: add more prominent failure notice on slogtest error

Signed-off-by: Spike Curtis <spike@coder.com>

* reinstated Fatal logs calling tb.Fatal

Signed-off-by: Spike Curtis <spike@coder.com>

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Signed-off-by: Spike Curtis <spike@coder.com>

* feat: ignore context.Canceled by default in slogtest

Signed-off-by: Spike Curtis <spike@coder.com>

* code review suggestions

Signed-off-by: Spike Curtis <spike@coder.com>

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Signed-off-by: Spike Curtis <spike@coder.com>

* chore(.github): update actions/upload-artifacts

Signed-off-by: Spike Curtis <spike@coder.com>

Currently, if a field like `sql.NullInt32` has `Valid: False`, `sloghuman` will export it's value as `<nil>`, regardless of it's `String`.
This is because it checks `(driver.Valuer).Value()`.

However, `slogjson` currently sets the value to the json string of the raw struct:
```json
{
  "fields": {
      "Code": "{Int32:0 Valid:false}",
      "ValidCode": "{Int32:12 Valid:true}"
  }
}
```

This PR handles this case by first checking if the type implements `sql/driver.Valuer`. If `Valid` is `false` then a JSON `null` value is produced:
```json
{
  "fields": {
      "Code": null,
      "ValidCode": 12
  }
}
```
This matches the behaviour of `sloghuman`.

This is technically a breaking change, as these types are now `T | null` instead of `String`, where `T` is the corresponding JSON type of `sql.Null<V>`