Make the experimental SwarmBucket bot use the SkiaTriggers pool

infra/project-config/cr-buildbucket.cfg

 # Defines buckets on cr-buildbucket.appspot.com, used to schedule builds
 # on buildbot. In particular, CQ uses some of these buckets to schedule tryjobs.
 #
 # See http://luci-config.appspot.com/schemas/projects:buildbucket.cfg for
 # schema of this file and documentation.
 #
 # Please keep this list sorted by bucket name.
 
 buckets {
   name: "master.client.skia"
@@ skipping 71 matching lines @@
   }
   acls {
     role: WRITER
     group: "service-account-skia-master"
   }
 
   swarming {
     hostname: "chromium-swarm.appspot.com"
     common_dimensions {
       key: "pool"
-      value: "Skia"
+      value: "SkiaTriggers"
     }
     common_swarming_tags: "master:master.client.skia.fyi"
     builders {
       name: "Build-Ubuntu-GCC-x86_64-Release-Swarmbucket"
       swarming_tags: "builder:Build-Ubuntu-GCC-x86_64-Release-Swarmbucket"
       swarming_tags: "allow_milo:1"
       dimensions {
         key: "os"
         value: "Linux"
       }
       dimensions {
         key: "gpu"
         value: "none"
       }
       recipe {
         repository: "https://skia.googlesource.com/skia.git"
         name: "swarm_trigger"
       }
     }
   }
 }