更新 'defaults'

defaults

@@ -1,6 +1,6 @@
 {   
     "gatk_docker":"registry.cn-shanghai.aliyuncs.com/shaolab2023_docker/gatk4:4.5.0.0_1",
     "gatk4_database":"oss://database-shaolab/gatk4_database/",
-    "gatk_cluster":"OnDemand bcs.es.r.4xlarge img-ubuntu-vpc",
+    "gatk_cluster":"OnDemand bcs.es.r.2xlarge img-ubuntu-vpc",
     "disk_size":"300"
 }