Remove KeepaliveRequestPriority entry from the testing config.

Bug: 1126640
Change-Id: I546ad3eb3c63e14b0e0290f0e1e6151ac5c52565
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2627998
Commit-Queue: Caitlin Fischer <caitlinfischer@google.com>
Reviewed-by: Yutaka Hirano <yhirano@chromium.org>
Cr-Commit-Position: refs/heads/master@{#843534}

testing/variations/fieldtrial_testing_config.json

@@ -3891,27 +3891,6 @@
             ]
         }
     ],
-    "KeepaliveRequestPriority": [
-        {
-            "platforms": [
-                "android",
-                "android_weblayer",
-                "android_webview",
-                "chromeos",
-                "linux",
-                "mac",
-                "windows"
-            ],
-            "experiments": [
-                {
-                    "name": "Enabled_20191107",
-                    "enable_features": [
-                        "SetLowPriorityForBeacon"
-                    ]
-                }
-            ]
-        }
-    ],
     "KeyboardAccessoryPasswordIPH": [
         {
             "platforms": [