Prevent infinite recursion within Tensor.__repr__ (#120206)
`Tensor.__repr__` calls functions which can perform logging which ends up logging `self` (with `__repr__`) causing an infinite loop. Instead of logging all the args in FakeTensor.dispatch log the actual parameters (and use `id` to log the tensor itself).
The change to torch/testing/_internal/common_utils.py came up during testing - in some ways of running the test parts was `('test', 'test_testing.py')` and so `i` was 0 and we were doing a join on `()` which was causing an error.
Repro:
```
import torch
from torch.testing import make_tensor
from torch._subclasses.fake_tensor import FakeTensor, FakeTensorMode
t = torch.sparse_coo_tensor(((0, 1), (1, 0)), (1, 2), size=(2, 2))
t2 = FakeTensor.from_tensor(t, FakeTensorMode())
print(repr(t2))
```
and run with `TORCH_LOGS=+all`
Pull Request resolved: https://github.com/pytorch/pytorch/pull/120206
Approved by: https://github.com/yanboliang, https://github.com/pearu
