Disable Xcode Debug tests (#132398)

Temporarily removes Xcode debug tests. 

Xcode tests are currently failing in CI for some infra-related issues. I have a fix for it (https://github.com/flutter/flutter/pull/132318) that I confirmed worked in presubmit, but I think the logic is better suited to live in recipes. However, it's going to be a bit of a learning curve to update recipes and might take me a couple days so disabling them in the meantime.

Tracking issue to readd when ready: https://github.com/flutter/flutter/issues/132309

.ci.yaml

@@ -3685,16 +3685,6 @@ targets:
         ["devicelab", "ios", "mac"]
       task_name: flutter_gallery_ios__start_up
 
-  - name: Mac_ios flutter_gallery_ios__start_up_xcode_debug
-    recipe: devicelab/devicelab_drone
-    presubmit: false
-    timeout: 60
-    properties:
-      tags: >
-        ["devicelab", "ios", "mac"]
-      task_name: flutter_gallery_ios__start_up_xcode_debug
-    bringup: true
-
   - name: Mac_ios flutter_view_ios__start_up
     recipe: devicelab/devicelab_drone
     presubmit: false
@@ -3762,16 +3752,6 @@ targets:
         ["devicelab", "ios", "mac"]
       task_name: integration_ui_ios_driver
 
-  - name: Mac_ios integration_ui_ios_driver_xcode_debug
-    recipe: devicelab/devicelab_drone
-    presubmit: false
-    timeout: 60
-    properties:
-      tags: >
-        ["devicelab", "ios", "mac"]
-      task_name: integration_ui_ios_driver_xcode_debug
-    bringup: true
-
   - name: Mac_ios integration_ui_ios_frame_number
     recipe: devicelab/devicelab_drone
     presubmit: false