Limit the max number of concurrent connections to remote cache/executor. By default the value is 100. Setting this to 0 means no limitation. For HTTP remote cache, one TCP connection could handle one request at one time, so Bazel could make up to --remote_max_connections concurrent requests. For gRPC remote cache/executor, one gRPC channel could usually handle 100+ concurrent requests, so Bazel could make around `--remote_max_connections * 100` concurrent requests.