Do brew update for xcode images

fkorotkov · fkorotkov · commit edba4cdf771c · 2018-10-30T09:26:55.000-04:00
diff --git a/templates/mojave-xcode.json b/templates/mojave-xcode.json
@@ -23,6 +23,13 @@
       ],
       "type": "shell"
     },
+    {
+      "inline": [
+        "brew --version",
+        "brew update"
+      ],
+      "type": "shell"
+    },
     {
       "environment_vars": [
         "FASTLANE_USER={{user `fastlane_user`}}",
