Update name of DisableFirstRunAutoImport default experiment to match finch config

testing/variations/fieldtrial_testing_config.json

 {
     "AndroidSessionNotifications": [
         {
             "platforms": [
                 "android"
             ],
             "experiments": [
                 {
                     "name": "Disabled"
                 }
@@ skipping 462 matching lines @@
             ]
         }
     ],
     "DisableFirstRunAutoImport": [
         {
             "platforms": [
                 "win"
             ],
             "experiments": [
                 {
-                    "name": "DisableFirstRunAutoImport",
+                    "name": "AutoImportDisabled",
                     "enable_features": [
                         "DisableFirstRunAutoImport"
                     ]
                 }
             ]
         }
     ],
     "DisallowFetchForDocWrittenScriptsInMainFrame": [
         {
             "platforms": [
@@ skipping 2012 matching lines @@
                 {
                     "name": "Enabled",
                     "enable_features": [
                         "use-new-media-cache"
                     ]
                 }
             ]
         }
     ]
 }