fix(mgb): fix tensorrt runtimeopr get output var shape bug

GitOrigin-RevId: b830706a891e4859d8e6a0d3db337a2941577168

src/tensorrt/impl/tensorrt_runtime_opr.cpp

@@ -107,6 +107,7 @@ TensorRTRuntimeOpr::TensorRTRuntimeOpr(
 void TensorRTRuntimeOpr::get_output_var_shape(
         const TensorShapeArray& inp_shape, TensorShapeArray& out_shape) const {
     auto batch = inp_shape.at(0)[0];
+    m_manager.clear_trt_context();
     m_manager.create_trt_context(this->comp_node(), inp_shape, m_engine.get());
     auto get_mgb_shape = [&](int binding_idx) -> TensorShape {
         auto dims = m_engine->getBindingDimensions(binding_idx);