Remove field trial testing config for DataReductionProxyUseQuic experiment

since the experiment is now enabled by default

Bug: 	672334
Change-Id: I900bba6e31a6bdb2d2251e3758a1bba6b6c659b6
Reviewed-on: https://chromium-review.googlesource.com/747561Reviewed-by: Robert Kaplow <rkaplow@chromium.org>
Commit-Queue: Tarun Bansal <tbansal@chromium.org>
Cr-Commit-Position: refs/heads/master@{#512953}

testing/variations/fieldtrial_testing_config.json

@@ -1023,26 +1023,6 @@
             ]
         }
     ],
-    "DataReductionProxyUseQuic": [
-        {
-            "platforms": [
-                "android",
-                "chromeos",
-                "linux",
-                "mac",
-                "win"
-            ],
-            "experiments": [
-                {
-                    "name": "Enabled",
-                    "params": {
-                        "enable_quic_non_core_proxies": "true",
-                        "enable_warmup": "true"
-                    }
-                }
-            ]
-        }
-    ],
     "DecoupleTranslateLanguage": [
         {
             "platforms": [