Add imagemagick-pdf

[homerr]

---

• [x] I have read the contributing guideline and understand that I have made the correct modifications

---

Description:

Added the imagemagick-pdf package

Benefits of this PR and context:

Closes issue #426

How Has This Been Tested?

Source / References:

[LinuxServer-CI]

I am a bot, here are the test results for this PR: https://ci-tests.linuxserver.io/lspipepr/nextcloud/28.0.4-pkg-2390b34a-dev-d8d98c708cf6982f8f05e0324291fca572e3bf41-pr-428/index.html https://ci-tests.linuxserver.io/lspipepr/nextcloud/28.0.4-pkg-2390b34a-dev-d8d98c708cf6982f8f05e0324291fca572e3bf41-pr-428/shellcheck-result.xml	Tag	Passed
amd64-28.0.4-pkg-2390b34a-dev-d8d98c708cf6982f8f05e0324291fca572e3bf41-pr-428	✅
arm64v8-28.0.4-pkg-2390b34a-dev-d8d98c708cf6982f8f05e0324291fca572e3bf41-pr-428	✅