[skip e2e] Update L2 test case after the change of pymilvus (#15219)

Signed-off-by: NBinbin Lv <binbin.lv@zilliz.com>

tests/python_client/testcases/test_search_20.py

@@ -489,11 +489,11 @@ class TestCollectionSearchInvalid(TestcaseBase):
         collection_w = self.init_collection_general(prefix, True, 10, partition_num, is_index=True)[0]
         par = collection_w.partitions
         par_name = par[partition_num].name
+        par[partition_num].load()
         # 2. release partition
-        conn = self.connection_wrap.get_connection()[0]
-        conn.release_partitions(collection_w.name, [par_name])
+        par[partition_num].release()
         # 3. Search the released partition
-        log.info("test_search_release_partition: Searching specifying the released partition")
+        log.info("test_search_release_partition: Searching the released partition")
         limit = 10
         collection_w.search(vectors, default_search_field,
                             default_search_params, limit, default_search_exp,