Add plutil to optimize xml files (fixes a notice in the CI)

Not sure if these logs are public, but:
https://github.com/Macleykun/RedditFilter/actions/runs/10320117450/job/28569939756#:~:text=19-,%3D%3D%3E%20Notice%3A%20Neither%20plutil%2C%20ply%2C%20or%20libplist%2Dutils%20are%20installed,20,-dm.pl%3A%20building%20package%20%60com.level3tjg.redditfilter%3Aiphoneos%2Darm64

> Making stage for tweak RedditFilter…
==> Notice: Neither plutil, ply, or libplist-utils are installed, so XML plist files were not optimized.
dm.pl: building package `com.level3tjg.redditfilter:iphoneos-arm' in `./packages/com.level3tjg.redditfilter_1.1.6_iphoneos-arm.deb'

Adding this package fixes the notice. I notice the CI is a second or 2 slower but that probably varies between runs.

.github/workflows/build.yml

@@ -36,7 +36,7 @@ jobs:
         if: ${{ inputs.create_release }}
         run: |
           sudo apt update
-          sudo apt install -y build-essential checkinstall git autoconf automake libtool-bin rsync llvm xmlstarlet
+          sudo apt install -y build-essential checkinstall git autoconf automake libtool-bin rsync llvm xmlstarlet plutil
           curl -L https://github.com/libimobiledevice/libplist/releases/download/2.4.0/libplist-2.4.0.tar.bz2 | bzip2 -d | tar -x
           cd libplist*
           ./configure
@@ -120,4 +120,4 @@ jobs:
         with:
           draft: true
           files: packages/*
-          tag_name: v${{ steps.ipa_info.outputs.version }}-${{ steps.package_info.outputs.version }}
+          tag_name: v${{ steps.ipa_info.outputs.version }}-${{ steps.package_info.outputs.version }}