[AF] Remove AutofillUpstreamEditableCardholderName from fieldtrial conf.

Was set to ENABLED_BY_DEFAULT in
https://chromium-review.googlesource.com/c/chromium/src/+/2017911

Change-Id: Ib93f62d678007d38043b59575cb9ee73f80f84d9
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2036355
Commit-Queue: Ilya Sherman <isherman@chromium.org>
Reviewed-by: Ilya Sherman <isherman@chromium.org>
Cr-Commit-Position: refs/heads/master@{#738701}

testing/variations/fieldtrial_testing_config.json

@@ -1003,26 +1003,6 @@
             ]
         }
     ],
-    "AutofillUpstreamEditableCardholderName": [
-        {
-            "platforms": [
-                "android",
-                "chromeos",
-                "ios",
-                "linux",
-                "mac",
-                "windows"
-            ],
-            "experiments": [
-                {
-                    "name": "Enabled",
-                    "enable_features": [
-                        "AutofillUpstreamEditableCardholderName"
-                    ]
-                }
-            ]
-        }
-    ],
     "AutofillUpstreamEditableExpirationDate": [
         {
             "platforms": [