Switching to a more recent Xcode image on CI

AliSoftware · AliSoftware · commit 466bb2419820 · 2022-06-24T13:51:48.000+02:00
Especially use one that has ruby 2.7.4 installed
diff --git a/.buildkite/pipeline.yml b/.buildkite/pipeline.yml
@@ -1,7 +1,7 @@
 # Nodes with values to reuse in the pipeline.
 common_params:
   env: &xcode_image
-    IMAGE_ID: xcode-12.5.1
+    IMAGE_ID: xcode-13.4.1
   plugins:
   - &docker_plugin
     docker#v3.8.0:
