WebRTC: Reshuffle Mac slaves in client.webrtc

masters/master.client.webrtc/slaves.cfg

Index: masters/master.client.webrtc/slaves.cfg
diff --git a/masters/master.client.webrtc/slaves.cfg b/masters/master.client.webrtc/slaves.cfg
index 499dd9253e7f6d91b2c19b9757012cc3bdad172f..a110d934f94bc39e1df6ceb5f104cd94589e4405 100644
--- a/masters/master.client.webrtc/slaves.cfg
+++ b/masters/master.client.webrtc/slaves.cfg
@@ -140,15 +140,23 @@ slaves = [
       'iOS ARM64 Release',
       'Mac32 Debug',
       'Mac32 Release',
+    ],
+    'hostname': 'vm672-m3',
+  },
+  {
+    'master': 'WebRTC',
+    'os': 'mac',
+    'version': '10.8',
+    'bits': '64',
+    'builder': [
       'Mac64 Debug',
       'Mac64 Release',
       'Mac64 Debug (GN)',
       'Mac64 Release (GN)',
       'Mac Asan',
     ],
-    'hostname': 'vm%d-m3' % i,
-  } for i in range(672, 674)
-] + [
+    'hostname': 'vm673-m3',
+  },
   # Mac, bare-metal.
   {
     'master': 'WebRTC',