change to ARM macOS Semaphore agent (confluentinc#2504)

Author: cchristous

.semaphore/semaphore.yml

@@ -39,7 +39,7 @@ blocks:
     task:
       agent:
         machine:
-          type: s1-prod-macos-13-5-amd64
+          type: s1-prod-macos-13-5-arm64
       jobs:
         - name: 'Build and test'
           commands: