Should add fonts for CJK characters

[zx900930]

Describe the bug
The CJK characters was missing when creating PDFs.
Those characters are showing in browser because the browser's system does have those fonts.
The same bug as #864 but for CJK characters.

Screenshots
Editor:

PDF:

When check the PDF file. I found it was using DejaVu fonts that doesn't support CJK characters.

Solutions
Add CJK fonts(For example google's noto sans with CJK characters: https://github.com/googlefonts/noto-cjk) to the app image or mount it as a volume:
- ./crater/fonts/noto-cjk:/usr/share/fonts/truetype/noto
And additionally, adding a font selection option to the customization setting tab to customize the fonts in PDF.

Please complete the following information:

• Crater version: docker 6.0.6

Optional info

• OS: [docker]
• Browser: [chrome latest]