Remove ftz

Avoid ci errors

- Draft state.
- Unsure if correct, but a very simple and quick test gives the same
  result from pytorch.
- Note: Tensorflow result differs, both from dfdx and from pytorch.

Reference pytorch test:
```python
import torch

x = np.array([[[[0.1, 0.7], [0.3, 0.4]]]])
w = np.array([[[[-0.1, -0.3, 0.7], [0.8, -0.2, 0.1], [0.3, 0.4, -0.5]]]])

a = torch.nn.ConvTranspose2d(output_padding=0, in_channels=1, out_channels=1, kernel_size=3, stride=2, padding=1, bias = False)
b = torch.nn.ConvTranspose2d(output_padding=1, in_channels=1, out_channels=1, kernel_size=3, stride=2, padding=1, bias = False)

x = torch.from_numpy(x).float()
w0 = torch.from_numpy(w).float()

with torch.no_grad():
    a.weight = torch.nn.Parameter(w0)
    b.weight = torch.nn.Parameter(w0)

ya = a(x)
yb = b(x)

print(ya.size()) # torch.Size([1, 1, 3, 3])
print(yb.size()) # torch.Size([1, 1, 4, 4])

print(ya)
print(yb)
```