[skip ci]Add a class to get milvus system info (#8118)

Signed-off-by: Nyanliang567 <yanliang.qiao@zilliz.com>

tests/python_client/common/milvus_sys.py

+import ujson
+from pymilvus.grpc_gen import milvus_pb2 as milvus_types
+from pymilvus import connections
+
+sys_info_req = ujson.dumps({"metric_type": "system_info"})
+sys_statistics_req = ujson.dumps({"metric_type": "system_statistics"})
+sys_logs_req = ujson.dumps({"metric_type": "system_logs"})
+
+
+class MilvusSys:
+    def __init__(self, alias):
+        self.alias = alias
+        self.client = connections.get_connection(alias=self.alias)
+        if self.client is None:
+            raise Exception(f"Connection {alias} is disconnected or nonexistent")
+
+        with self.client._connection() as handler:
+            req = milvus_types.GetMetricsRequest(request=sys_info_req)
+            self.sys_info = handler._stub.GetMetrics(req, wait_for_ready=True, timeout=None)
+            req = milvus_types.GetMetricsRequest(request=sys_statistics_req)
+            self.sys_statistics = handler._stub.GetMetrics(req, wait_for_ready=True, timeout=None)
+            req = milvus_types.GetMetricsRequest(request=sys_logs_req)
+            self.sys_logs = handler._stub.GetMetrics(req, wait_for_ready=True, timeout=None)
+
+
+    @property
+    def build_version(self):
+        raise NotImplementedError()
+
+    @property
+    def deploy_mode(self):
+        raise NotImplementedError()
+
+    @property
+    def simd_type(self):
+        raise NotImplementedError()
+
+    @property
+    def query_nodes(self):
+        raise NotImplementedError()
+
+    @property
+    def data_nodes(self):
+        raise NotImplementedError()
+
+    @property
+    def index_nodes(self):
+        raise NotImplementedError()
+