[cr-buildbucket.cfg] Fix duplicate buildername.

R=nodir@chromium.org

Change-Id: If7d4793523d7ada7e08722b5442988568554d5c1
Reviewed-on: https://chromium-review.googlesource.com/959603Reviewed-by: Nodir Turakulov <nodir@chromium.org>
Commit-Queue: Robbie Iannucci <iannucci@chromium.org>
Cr-Commit-Position: refs/heads/master@{#542633}

infra/config/global/cr-buildbucket.cfg

@@ -891,7 +891,6 @@ buckets {
     builders { mixins: "linux-try" name: "cast_shell_audio_linux" }
     builders { mixins: "linux-try" name: "cast_shell_linux" }
     builders { mixins: "linux-try" name: "chromeos_amd64-generic_chromium_compile_only_ng" }
-    builders { mixins: "linux-try" name: "chromeos_amd64-generic_chromium_compile_only_ng" }
     builders { mixins: "linux-try" name: "chromeos_amd64-generic_variable" }
     builders { mixins: "linux-try" name: "chromeos_daisy_chromium_compile_only_ng" }
     builders { mixins: "linux-try" name: "chromeos_daisy_variable" }