winform读取PDF，Unable to load DLL 'pdfium(.dll/.dylib)'

PdfiumViewer库依赖于pdfium.dll，但其本身不提供pdfium.dll，需要引入额外的库，比如：

PdfiumViewer.Native.x86_64.v8-xfa

PdfiumViewer.Native.x86_64.no_v8-no_xfa

PdfiumViewer.Native.x86.v8-xfa

PdfiumViewer.Native.x86.no_v8-no_xfa