Export fails when paste with unknown color

[AntoLC]

Describe the bug

When we copy a text that has a style attach, and paste it in the doc, the export will then fails (pdf / odt / docx..).

How to reproduce

• Copy any text from github
• Paste it to a doc
• Export
• The export fails

Why

A paste color can be in rgb:

Problem location

BlockNote/packages/xl-pdf-exporter/src/pdf/pdfExporter.tsx

Lines 299 to 301 in d192b37

	: this.options.colors[
	props.backgroundColor as keyof typeof this.options.colors
	].background,

BlockNote/packages/xl-pdf-exporter/src/pdf/pdfExporter.tsx

Lines 305 to 307 in d192b37

	: this.options.colors[
	props.textColor as keyof typeof this.options.colors
	].text,

The array is possibly undefined, it should be something like:
this.options.colors?.[props.backgroundColor as keyof typeof this.options.colors]?.background

https://github.com/search?q=repo%3ATypeCellOS%2FBlockNote%20props.textColor%20as&type=code

Misc

• Node version:
• Package manager:
• Browser:
• I'm a sponsor and would appreciate if you could look into this sooner than later 💖

[AntoLC]

Btw, a comment has this color (rgb(237 180 0 / 40%)), so making a comment and trying to export will trigger an error.