rabbitmq_consistent_hash_exchange: Remove shard count for test suite

Without buildbuddy for parallelization and with the change in the parent
commit to reduce the number of cases, the suite now runs fast enough
that sharding is counterproductive.

Author: the-mikedavis

deps/rabbitmq_consistent_hash_exchange/BUILD.bazel

@@ -82,7 +82,6 @@ broker_for_integration_suites()
 
 rabbitmq_integration_suite(
     name = "rabbit_exchange_type_consistent_hash_SUITE",
-    shard_count = 7,
     runtime_deps = [
         "//deps/rabbitmq_amqp_client:erlang_app",
     ],