format-resources are not cleaned up after rendering

Bug description

I'm building an extension for formatting my thesis at Oxford. Let's say I have the following bare-bones extension:

title: Oxford Thesis Format
author: Benjamin Lee
version: 0.1.0
contributes:
  format:
    pdf:
      format-resources:
        - ociamthesis.cls

When I render the PDF on my Mac, it works but the .cls file isn't cleaned up as would be expected.

quarto check Output

[✓] Checking Quarto installation......OK
      Version: 1.0.28
      Path: /Applications/quarto/bin

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

[✓] Checking Python 3 installation....OK
      Version: 3.9.13
      Path: /usr/local/opt/python@3.9/bin/python3.9
      Jupyter: 4.8.1
      Kernels: corona, python3, squiggle, deep-rules, condo, julia-1.0, viroids, python37564bit620d0d3e6fc64febbcdac4f79a1dc46f, hla, mechwolf, krtd, javascript, krtd-binning

(\) Checking Jupyter engine render....dyld[45896]: Library not loaded: @executable_path/../.Python
  Referenced from: /Users/BenjaminLee/.virtualenvs/corona/bin/python3.7
  Reason: tried: '/Users/BenjaminLee/.virtualenvs/corona/bin/../.Python' (no such file), '/usr/local/lib/.Python' (no such file), '/usr/lib/.Python' (no such file)


Kernel died before replying to kernel_info
[✓] Checking Jupyter engine render....OK

quarto tools check Output

[✓] Inspecting tools

Tool         Status            Installed     Latest  
chromium     Not installed     ---           869685  
tinytex      Not installed     ---           v2022.07

Checklist

• formatted your issue so it is easier for us to read?
• included a minimal, fully reproducible example in a single .qmd file? Please provide the whole file rather than the snippet you believe is causing the issue.
• documented the quarto version you're running, by pasting the output from running quarto check in the "Quarto Check Output" text area?
• documented the version of the quarto tools you're running, by providing the output from running quarto tools check in the "Quarto Tools Check Output" text area?
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• upgraded to the latest version, including your versions of R, the RStudio IDE, and relevant R packages?