Run tests on either iOS 17 or iOS 18 (#166879)

Fixes https://github.com/flutter/flutter/issues/148968.

## Pre-launch Checklist

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responsibilities.
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we expect every widget to implement].
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- [x] I listed at least one issue that this PR fixes in the description
above.
- [x] I updated/added relevant documentation (doc comments with `///`).
- [x] I added new tests to check the change I am making, or this PR is
[test-exempt].
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Fixes] where supported.
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.ci.yaml

@@ -286,7 +286,7 @@ platform_properties:
         ]
       os: Mac-14
       cpu: x86
-      device_os: iOS-17
+      device_os: iOS-17|iOS-18
       $flutter/osx_sdk : >-
         {
           "sdk_version": "16c5032a"
@@ -304,7 +304,7 @@ platform_properties:
         ]
       os: Mac-14
       cpu: x86
-      device_os: iOS-17
+      device_os: iOS-17|iOS-18
       $flutter/osx_sdk : >-
         {
           "sdk_version": "16c5032a"
@@ -322,7 +322,7 @@ platform_properties:
         ]
       os: Mac-14
       cpu: arm64
-      device_os: iOS-17
+      device_os: iOS-17|iOS-18
       $flutter/osx_sdk : >-
         {
           "sdk_version": "16c5032a"
@@ -5380,7 +5380,7 @@ targets:
         ["devicelab", "ios", "mac"]
       task_name: flutter_gallery__transition_perf_e2e_ios
       drone_dimensions: >
-        ["device_os=iOS-17","os=Mac-14", "cpu=x86"]
+        ["device_os=iOS-17|iOS-18","os=Mac-14", "cpu=x86"]
 
   - name: Mac_ios animated_blur_backdrop_filter_perf_ios__timeline_summary
     recipe: devicelab/devicelab_drone