Add supported branch chrome/m143, remove chrome/m139

Change-Id: Iacc044a67dff880a90834649e9dae2a27d108638
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/1086477
Reviewed-by: Eric Boren <borenet@google.com>
diff --git a/supported-branches.json b/supported-branches.json
index c0779f2..88e41db 100644
--- a/supported-branches.json
+++ b/supported-branches.json
@@ -5,10 +5,6 @@
       "owner": "skiabot@google.com"
     },
     {
-      "ref": "refs/heads/chrome/m139",
-      "owner": "sharaks@google.com"
-    },
-    {
       "ref": "refs/heads/chrome/m140",
       "owner": "sharaks@google.com"
     },
@@ -19,6 +15,10 @@
     {
       "ref": "refs/heads/chrome/m142",
       "owner": "sharaks@google.com"
+    },
+    {
+      "ref": "refs/heads/chrome/m143",
+      "owner": "hcm@google.com"
     }
   ]
 }
\ No newline at end of file