Reverts "[ci] Run check_podspecs on arm Mac bots" (#5909)

Reverts #5885
Initiated by: jmagman
This change reverts the following previous change:
Original Description:
Fixes flutter/flutter#141493

Author: auto-submit[bot]

.ci.yaml

@@ -1062,7 +1062,9 @@ targets:
         }
 
   ### iOS+macOS tasks ###
-  # TODO(jmagman): Remove when repo_checks is no longer in bringup.
+  # TODO(stuartmorgan): Move this to ARM once google_maps_flutter has ARM
+  # support. `pod lint` makes a synthetic target that doesn't respect the
+  # pod's arch exclusions, so fails to build.
   - name: Mac_x64 check_podspecs
     recipe: packages/packages
     timeout: 30
@@ -1071,15 +1073,6 @@ targets:
       version_file: flutter_master.version
       target_file: macos_check_podspecs.yaml
 
-  - name: Mac_arm64 repo_checks
-    recipe: packages/packages
-    timeout: 30
-    bringup: true
-    properties:
-      add_recipes_cq: "true"
-      version_file: flutter_master.version
-      target_file: macos_check_podspecs.yaml
-
   ### macOS desktop tasks ###
   # macos-platform_tests builds all the packages on ARM, so this build is run
   # on Intel to give us build coverage of both host types.