Repository: stable-diffusion-webui
Issue: [Bug]:  Xformers available but not
Labels: bug-report

### Is there an existing issue for this?

- [X] I have searched the existing issues and checked the recent builds/commits

### What happened?

xformers is installed and available in my conda env yet not.  

To demonstrate that xformers is working:
`python -m xformers.info`
```
xFormers 0.0.15+ea1048b.d20221220
memory_efficient_attention.cutlassF:               available
memory_efficient_attention.cutlassB:               available
memory_efficient_attention.flshattF:               available
memory_efficient_attention.flshattB:               available
memory_efficient_attention.smallkF:                available
memory_efficient_attention.smallkB:                available
memory_efficient_attention.tritonflashattF:        available
memory_efficient_attention.tritonflashattB:        available
swiglu.fused.p.cpp:                                available
is_triton_available:                               True
is_functorch_available:                            False
pytorch.version:                                   1.13.0+cu117
pytorch.cuda:                                      available
gpu.compute_capability:                            8.6
gpu.name:                                          NVIDIA GeForce RTX 3080 Ti
```
But when running

`bash <(wget -qO- https://raw.githubusercontent.com/AUTOMATIC1111/stable-diffusion-webui/master/webui.sh)`

Im getting: 
```
Dreambooth revision: c678a431b5d79ba7e1c38d7629ca7e0c79166a1f
SD-WebUI revision: 685f9631b56ff8bd43bce24ff5ce0f9a0e9af490

Checking Dreambooth requirements...
[+] bitsandbytes version 0.35.0 installed.
[+] diffusers version 0.10.2 installed.
[+] transformers version 4.25.1 installed.
[ ] xformers version N/A installed.
[+] torch version 1.12.1+cu113 installed.
[+] torchvision version 0.13.1+cu113 installed.
#######################################################################################################

Launching Web UI with arguments: 
No module 'xformers'. Proceeding without it.
```

### Steps to reproduce the problem

```
mamba create -n sd_au1111_v2 python=3.10.6 pytorch torchvision pytorch-lightning torchaudio pytorch-cuda diffusers transformers ftfy -c pytorch -c nvidia  -y
mamba activate sd_au1111_v2
pip install ninja triton functorch
pip install -v -U git+https://github.com/facebookresearch/xformers.git@main#egg=xformers

bash <(wget -qO- https://raw.githubusercontent.com/AUTOMATIC1111/stable-diffusion-webui/master/webui.sh)
```

Ubuntu 22.04
nvcc: NVIDIA (R) Cuda compiler driver
Cuda compilation tools, release 11.7, V11.7.99
Build cuda_11.7.r11.7/compiler.31442593_0


### What should have happened?

Assuming xformers should be available

### Commit where the problem happens

685f9631b56ff8bd43bce24ff5ce0f9a0e9af490

### What platforms do you use to access UI ?

Linux

### What browsers do you use to access the UI ?

Mozilla Firefox

### Command Line Arguments

```Shell
`./webui.sh --xformers` fails to install as well

: Couldn't install xformers.
stderr:   error: subprocess-exited-with-error
```


### Additional information, context and logs

_No response_