Switch back to installing ImageMagick in CI (#349)

Author: mokagio

.buildkite/pipeline.yml

@@ -24,8 +24,10 @@ steps:
   - label: "🧪 Build and Test"
     key: test
     command: |
+      # We only need this for tasks running on a Mac
+      brew install pkg-config git-lfs libxml2 imagemagick@6
+
       echo "--- :git: Setting up git-lfs"
-      brew install git-lfs
       git-lfs install
 
       echo "--- :rubygems: Setting up Gems"

CHANGELOG.md

@@ -18,7 +18,7 @@ _None_
 
 ### Internal Changes
 
-* Speed up our CI by removing now-useless installation of ImageMagick on CI to run the "Build and Test" step. [#348]
+_None_
 
 ## 4.0.0