Add cpu dimension support in ci yaml

Change-Id: Ib69f78991827d39b2aaee0a75f0c0d37f2dc2621
Bug: https://github.com/flutter/flutter/pull/101871, https://github.com/flutter/flutter/issues/101861
Reviewed-on: https://flutter-review.googlesource.com/c/infra/+/29061
Reviewed-by: Casey Hillers <chillers@google.com>
Commit-Queue: Keyong Han <keyonghan@google.com>
diff --git a/config/lib/ci_yaml/ci_yaml.star b/config/lib/ci_yaml/ci_yaml.star
index 24857fa..37c2d9e 100644
--- a/config/lib/ci_yaml/ci_yaml.star
+++ b/config/lib/ci_yaml/ci_yaml.star
@@ -328,7 +328,7 @@
         # Set dimensions dimensions from properties.
         if platform in dimensions:
             target_args["dimensions"] = dimensions[platform]
-        dimension_key_list = ("device_type", "device_os", "mac_model", "cores")
+        dimension_key_list = ("device_type", "device_os", "mac_model", "cores", "cpu")
         for dimension_key in dimension_key_list:
             if dimension_key in merged_properties:
                 target_args["dimensions"][dimension_key] = str(merged_properties[dimension_key])