relative path in includegraphics not working

[amael-ls]

Description

Hello,

In this stackoverflow post, it is shown that the command includegraphics will fail in a TikZ picture when using relative path rather than absolute. This is because the image is created in a temporary folder that does not have access to the included file relatively. Would it be possible to change this feature?

MWE

Here is an example that shows the problem:

---
title: "A tikz test"
pdf-engine: lualatex
keep-tex: true
filters:
  - diagram
diagram:
  engine:
    tikz:
      execpath: lualatex
      header-includes:
        \usepackage{graphicx}
format:
  pdf:
    include-in-header:
      - text: |
          \usepackage{graphicx}
          \usepackage{tikz}
---

## Test section

See @fig-test below.

::: {#fig-test}

```tikz
\begin{tikzpicture}
    \node (orig) at (0, 0) {\includegraphics{figTest.png}};
\end{tikzpicture}
```

A test figure

:::

Expected

A pdf with the figure figTest.png included.

Happening

LaTeX Warning: File `figTest.png' not found on input line 7.
! Package luatex.def Error: File `figTest.png' not found: using draft setting.

Many thanks for making it possible to use TikZ in Quarto!