Remove external link arrows in icons (i.e., in the header of the sidebar)

[ateucher]

The auto-generated arrow icons look funny next to the github and globe icons:

These are enabled globally in _quarto.yml, maybe there is a way to disable it in specific cases

[ateucher]

This issue appears to be fixed in latest Quarto (see quarto-dev/quarto-cli#6432), and the external link icons don't show up for me locally. Perhaps the github action is using an older Quarto