fix return type (#5548)

* fix return type

* auto format by CI

Co-authored-by: oneflow-ci-bot <ci-bot@oneflow.org>
Co-authored-by: oneflow-ci-bot <69100618+oneflow-ci-bot@users.noreply.github.com>

oneflow/core/kernel/sink_tick_kernel.h

@@ -29,9 +29,7 @@ class SinkTickKernel final : public KernelIf<DeviceType::kCPU> {
  private:
   void ForwardDataContent(const KernelCtx& ctx,
                           std::function<Blob*(const std::string&)> BnInOp2Blob) const override {}
-  const PbMessage& GetCustomizedOpConf() const override {
-    return this->op_conf().source_tick_conf();
-  }
+  const PbMessage& GetCustomizedOpConf() const override { return this->op_conf().sink_tick_conf(); }
 };
 
 }  // namespace oneflow