pdf transform: bold and italics do not work

[jeromesimeon]

Bug Report 🐛

Bold and italics are not exported to pdf.

Steps to Reproduce

Taking the following markdown document:

This is _foo_ and **bar** and **_foobar_**

And exporting it with:

markus transform --from markdown_cicero --to pdf --input test.md --output test.pdf

Results in the following pdf where italics and bold are absent.

test.pdf

[jeromesimeon]

Here is the relevant part of the pdfmake JSON:

{
  "style": "Document",
  "content": [
    {
      "style": "Paragraph",
      "text": [
        {
          "text": "This is "
        },
        {
          "style": "Emph",
          "text": [
            {
              "text": "foo"
            }
          ],
          "italics": true
        },
        {
          "text": " and "
        },
        {
          "style": "Strong",
          "text": [
            {
              "text": "bar"
            }
          ],
          "bold": true
        },
        {
          "text": " and "
        },
        {
          "style": "Strong",
          "text": [
            {
              "style": "Emph",
              "text": [
                {
                  "text": "foobar"
                }
              ],
              "italics": true
            }
          ],
          "bold": true
        }
      ],
      "margin": [
        0,
        5
      ]
    }
  ],