Change kernel-builder ref to specific commit

Updated the reference for the kernel-builder repository to a specific commit.

Author: mfuntowicz

.github/workflows/build-pr-windows.yaml

@@ -69,7 +69,7 @@ jobs:
         uses: actions/checkout@v5
         with:
           repository: huggingface/kernel-builder
-          ref: 3b6264e  # todo(mfuntowicz): remove this when merged in kernel-builder
+          ref: 3b6264ec69ef7d336ba7be6d86a137ef238f7e30  # todo(mfuntowicz): remove this when merged in kernel-builder
           path: kernel-builder
 
       - name: Cache Rust build