CI: Get openblas natively

Author: HaoZeke

.github/workflows/freethreading_tests.yml

@@ -15,9 +15,13 @@ jobs:
           enable-cache: false
       - name: Set up Python
         run: uv python install
+      - name: Install OpenBLAS
+        run: |
+          sudo apt update
+          sudo apt install -y libopenblas-dev
       - name: Install Dependencies
         run: |
-          uv pip install numpy scipy pytest-timeout pytest-durations pytest-run-parallel openblas
+          uv pip install numpy scipy pytest-timeout pytest-durations pytest-run-parallel
       - name: Build
         run: |
           uv pip install -v .