Fix graph viewer to proto (#11862)
* Add test for case where main const initialier in subgraph
* update test to use trt ep
* add initializer when converting from graph viewer to proto
* add comments
* add comments
* add comments
* only add initialier that is outer scope value
* make including outer scope value optional
* modify python format
* modify python format
* modify python format
* Remove test
* remove redundant argument
