Can't republish qmd files containing Graphviz or Mermaids diagrams on Confluence

Bug description

When I republish qmd files containing mermaids or graphviz diagrams to confluence, I get an error.

• This doesn't happen on the initial publication of these files
• It doesn't happen when I republish qmd files that don't have these types of diagram

Steps to reproduce

• First publish the example qmd on confluence -> this should work fine
  (my command was quarto publish confluence --no-browser test.qmd )
• Next edit the qmd locally, I just added a few words below the diagram code block
• republish to confluence with the same code as above

# Title

```{dot}
//| label: fig-simplegraph
//| fig-width: 3
//| fig-cap: |
//|   A simple graph

graph Graph {
  layout=neato
  TA -- AT ;
  AT -- TA;
  AT -- TT;
  TT -- TA;
  AA -- AT;
  TA -- AA;

}

```

Expected behavior

Should render and publish as normal.

Actual behavior

ERROR: API Error: 400 - Bad Request

Stack trace:
at ConfluenceClient.handleResponse (file:///opt/quarto/bin/quarto.js:105438:19)
at ConfluenceClient.fetch (file:///opt/quarto/bin/quarto.js:105243:25)
at eventLoopTick (ext:core/01_core.js:183:11)
at async ConfluenceClient.updateContent (file:///opt/quarto/bin/quarto.js:105376:25)
at async updateContent (file:///opt/quarto/bin/quarto.js:105703:32)
at async doOperation (file:///opt/quarto/bin/quarto.js:105817:33)
at async withSpinner (file:///opt/quarto/bin/quarto.js:75270:16)
at async doWithSpinner (file:///opt/quarto/bin/quarto.js:104791:12)
at async publishDocument (file:///opt/quarto/bin/quarto.js:105828:13)
at async Object.publish5 [as publish] (file:///opt/quarto/bin/quarto.js:105969:49

Your environment

Quarto version: Quarto 1.4.549
OS: Ubuntu 22.04.4 LTS (via WSL2 for Windows 11)
IDE: VSCode 1.88.1 Windows

Quarto check output

Quarto 1.4.549
[✓] Checking versions of quarto binary dependencies...
      Pandoc version 3.1.11: OK
      Dart Sass version 1.69.5: OK
      Deno version 1.37.2: OK
[✓] Checking versions of quarto dependencies......OK
[✓] Checking Quarto installation......OK
      Version: 1.4.549
      Path: /opt/quarto/bin

[✓] Checking tools....................OK
      TinyTeX: v2024.04
      Chromium: (not installed)

[✓] Checking LaTeX....................OK
      Using: TinyTex
      Path: /home/cormac/.TinyTeX/bin/x86_64-linux
      Version: 2024

[✓] Checking basic markdown render....OK

[✓] Checking Python 3 installation....OK
      Version: 3.10.13 (Conda)
      Path: /home/cormac/programs/mambaforge/bin/python
      Jupyter: 5.7.1
      Kernels: python3

[✓] Checking Jupyter engine render....OK

[✓] Checking R installation...........(None)

      Unable to locate an installed version of R.
      Install R from https://cloud.r-project.org/

Reproduce the failure with the provided test.qmd using quarto publish confluence --no-browser test.qmd, first publishing and then republishing after a text edit. Inspect the ConfluenceClient.updateContent path shown in the stack trace and verify that documents containing Graphviz or Mermaid diagrams can be republished successfully.