[iOS] Run SVC tests on 12 cores machines

Change-Id: I8e8bda835504ac1440c7d65bfc62ecbb619fce54
Bug: None
No-Try: true
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/281161
Commit-Queue: Jeremy Leconte <jleconte@google.com>
Auto-Submit: Jeremy Leconte <jleconte@google.com>
Reviewed-by: Christoffer Jansson <jansson@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#38504}

infra/specs/client.webrtc.json

@@ -10557,6 +10557,7 @@
           ],
           "dimension_sets": [
             {
+              "cores": "12",
               "cpu": "x86-64",
               "os": "Mac-12"
             }
@@ -11535,6 +11536,7 @@
           ],
           "dimension_sets": [
             {
+              "cores": "12",
               "cpu": "x86-64",
               "os": "Mac-12"
             }
@@ -12513,6 +12515,7 @@
           ],
           "dimension_sets": [
             {
+              "cores": "12",
               "cpu": "x86-64",
               "os": "Mac-12"
             }

infra/specs/test_suites.pyl

@@ -171,7 +171,7 @@
         'mixins': ['xcode_parallelization']
       },
       'svc_tests': {
-        'mixins': ['shards-4'],
+        'mixins': ['shards-4', 'cores-12'],
       },
       'system_wrappers_unittests': {},
       'test_support_unittests': {},

infra/specs/tryserver.webrtc.json

@@ -3469,6 +3469,7 @@
           ],
           "dimension_sets": [
             {
+              "cores": "12",
               "cpu": "x86-64",
               "os": "Mac-12"
             }
@@ -4447,6 +4448,7 @@
           ],
           "dimension_sets": [
             {
+              "cores": "12",
               "cpu": "x86-64",
               "os": "Mac-12"
             }
@@ -5425,6 +5427,7 @@
           ],
           "dimension_sets": [
             {
+              "cores": "12",
               "cpu": "x86-64",
               "os": "Mac-12"
             }