Use different command to convert images with ImageMagick

[ethanliu24]

Proposed Changes

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In recent versions of ImageMagick, the convert command is deprecated, and it is recommended to use the magick command. This PR uses the recommended command to convert graphs to display in the export modal.
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Type of Change

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Type	Applies?
🚨 Breaking change (fix or feature that would cause existing functionality to change)
✨ New feature (non-breaking change that adds functionality)
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📦 Dependency update (change that updates a dependency)
🔧 Internal (change that only affects developers or continuous integration)	X

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Questions and Comments

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[david-yz-liu]

@ethanliu24 great work, and in particular the research for fixing the text-anchor value.

[david-yz-liu]

@ethanliu24 oops, there is one thing I forgot to flag for you. Currently there's a check on the server code that the convert executable is installed. This should also be changed to magick. Look at the Haskell setup files for the place I'm referring to.

[david-yz-liu]

delete this line

[david-yz-liu]

revert the changes on this line (GitHub is highlighting trailing whitespace here; I recommend configuring your text editor to automatically strip trailing whitespace)

[david-yz-liu]

keep this line (put the sudo apt-get install command immediately below it)

[david-yz-liu]

I meant the existing command that installed texlive-latex-base (just running sudo apt-get install without additional arguments doesn't do much)

[ethanliu24]

I'm not too familiar with linux (yet), but is there a reason for installing latex first before imagemagick?

[david-yz-liu]

@ethanliu24 good work! LaTeX didn't need to be installed imagemagick (it could be installed afterwards), and my comments were about keeping the apt-get commands together, rather than separated.