Update examples/stable_diffusion/README.md (#1539)

## Describe your changes
Update ONNX Runtime's installation instructions

## Checklist before requesting a review
- [N/A ] Add unit tests for this change.
- [N/A ] Make sure all tests can pass.
- [ ] Update documents if necessary.
- [N/A ] Lint and apply fixes to your code by running `lintrunner -a`
- [ N/A] Is this a user-facing change? If yes, give a description of
this change to be included in the release notes.
- [ N/A] Is this PR including examples changes? If yes, please remember
to update [example
documentation](https://github.com/microsoft/Olive/blob/main/docs/source/examples.md)
in a follow-up PR.

## (Optional) Issue link

examples/stable_diffusion/README.md

@@ -60,7 +60,8 @@ This example requires the latest onnxruntime-gpu code which can either be built
 pip uninstall -y onnxruntime onnxruntime-gpu onnxruntime-directml ort-nightly ort-nightly-gpu ort-nightly-directml
 
 # install onnxruntime-gpu nightly build
-pip install ort-nightly-gpu --extra-index-url https://aiinfra.pkgs.visualstudio.com/PublicPackages/_packaging/ORT-Nightly/pypi/simple/
+pip install -r https://raw.githubusercontent.com/microsoft/onnxruntime/refs/heads/main/requirements.txt
+pip install onnxruntime-gpu --pre --index-url https://aiinfra.pkgs.visualstudio.com/PublicPackages/_packaging/ORT-Nightly/pypi/simple/
 ```
 
 ##### Install other dependencies