update module list (#4057)

Author: zoooo0820

docs/api/gen_doc.py

@@ -414,6 +414,7 @@ def set_api_sketch():
         paddle.nn.utils,
         paddle.static,
         paddle.static.nn,
+        paddle.signal,
         paddle.io,
         paddle.jit,
         paddle.metric,
@@ -427,6 +428,7 @@ def set_api_sketch():
         paddle.utils.profiler,
         paddle.utils.cpp_extension,
         paddle.utils.unique_name,
+        paddle.utils.dlpack,
         paddle.sysconfig,
         paddle.vision,
         paddle.vision.datasets,