[`test` / `peft`] Fix silent behaviour on PR tests (#5852)

Update pr_test_peft_backend.yml

.github/workflows/pr_test_peft_backend.yml

@@ -45,7 +45,7 @@ jobs:
       run: |
         apt-get update && apt-get install libsndfile1-dev libgl1 -y
         python -m pip install -e .[quality,test]
-        if [ "${{ matrix.lib-version }}" == "main" ]; then
+        if [ "${{ matrix.lib-versions }}" == "main" ]; then
             python -m pip install -U git+https://github.com/huggingface/peft.git
             python -m pip install -U git+https://github.com/huggingface/transformers.git
             python -m pip install -U git+https://github.com/huggingface/accelerate.git