[fx2trt] Convert to tuple is output_size of adaptive avg pool is an integer (#70144)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/70144
It can be an integer and in this case we need to extend it.
Test Plan:
Added a unit test.
```
RemoteExecution session id: reSessionID-d97b46e3-20d1-4f5c-a166-4efcf1579352-tpx
Started reporting to test run: https://www.internalfb.com/intern/testinfra/testrun/8162774391775638
✓ ListingSuccess: caffe2/test/fx2trt/converters:test_adaptive_avgpool - main (9.454)
✓ Pass: caffe2/test/fx2trt/converters:test_adaptive_avgpool - test_adaptive_avgpool_with_dynamic_shape (caffe2.test.fx2trt.converters.acc_op.test_adaptive_avgpool.TestAdaptiveAvgPoolConverter) (16.083)
✓ Pass: caffe2/test/fx2trt/converters:test_adaptive_avgpool - test_adaptive_avgpool_1 (caffe2.test.fx2trt.converters.acc_op.test_adaptive_avgpool.TestAdaptiveAvgPoolConverter) (16.349)
✓ Pass: caffe2/test/fx2trt/converters:test_adaptive_avgpool - test_adaptive_avgpool_2 (caffe2.test.fx2trt.converters.acc_op.test_adaptive_avgpool.TestAdaptiveAvgPoolConverter) (16.543)
✓ Pass: caffe2/test/fx2trt/converters:test_adaptive_avgpool - test_adaptive_avgpool_0 (caffe2.test.fx2trt.converters.acc_op.test_adaptive_avgpool.TestAdaptiveAvgPoolConverter) (16.651)
Summary
Pass: 4
ListingSuccess: 1
```
Reviewed By: wushirong
Differential Revision: D33200773
fbshipit-source-id: 8c10d644982a4723a78f8615d8bcdbc3968790db
