Update the SixLabors package

[AquanPJCA]

Can we update the SixLabors package as there is a security vulnerability.

[zur003]

I suggest you consider using PDFSharp rather than PdfSharpCore.

[tossnet]

I suggest you consider using PDFSharp rather than PdfSharpCore.

@zur003 Is it also free to use?

[zur003]

I suggest you consider using PDFSharp rather than PdfSharpCore.

@zur003 Is it also free to use?

Yes, it's open source under the MIT license.

[jochenwezel]

I like to stay at PdfSharpCore since it doesn't depend on windows platform. So back to the origin request: it would be great to see the SixLabors package reference being refreshed to a newer version without security warning :-)

[jochenwezel]

I already see there is a pull request #476 which might fix this issue. Please can somebody review/merge it?