Breaking changes in a minor release! (1.3.0)

[Expurple]

I updated from 1.2.7 to v1.3.0 and the build failed. This is because #204 introduced many breaking changes:

• Removed public umya_spreadsheet::writer::csv::XlsxError
• Removed public umya_spreadsheet::writer::xlsx::XlsxError (my code references it)
• Removed public umya_spreadsheet::reader::xlsx::XlsxError (my code references it)
• Changes to variants of public CellRawValue
• Added parameter to public CellValue::set_error
• Maybe something else? Consider running cargo-semver-checks against your pull requests to get a more accurate list.

Please consider yanking 1.3.0 from crates.io and releasing version 2.0.0 to reflect the breaking changes.