Reland "[RPC] Use qualified name str directly in RPC torch script code path" (#34962)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/34962
Relanding #34733. Fix is in https://github.com/pytorch/pytorch/pull/34988.
Test Plan:
```
buck test mode/dev-nosan //caffe2/test/distributed/rpc:rpc_fork
```
```
buck test mode/dev-nosan //caffe2/test/distributed/rpc/jit:rpc_fork
buck build mode/dev-nosan //caffe2/test/distributed/rpc/jit:rpc_fork \
&& buck-out/gen/caffe2/test/distributed/rpc/jit/rpc_fork\#binary.par \
-r test_return_local_script_class_rref_in_py_and_use_in_script
buck build mode/dev-nosan //caffe2/test/distributed/rpc/jit:rpc_fork \
&& buck-out/gen/caffe2/test/distributed/rpc/jit/rpc_fork\#binary.par \
-r test_return_local_script_module_rref_in_py_and_use_in_script
```
```
buck test mode/dev //caffe2/test/distributed/rpc/jit:rpc_fork_thrift -- test_return_local_script_module_rref_in_py_and_use_in_script
```
Differential Revision: D7778113
fbshipit-source-id: b830c03ac9463075fca248eba75be364b0e8b080
