Use bash for windows

Signed-off-by: laurentsimon <[email protected]>

.github/workflows/unit_tests.yml

@@ -6,6 +6,12 @@ on:
 
 permissions: {}
 
+defaults:
+  run:
+    # The default shell on Windows is `pwsh`. However, it doesn't expand
+    # asterisks. That's why we always use `bash`.
+    shell: bash
+
 jobs:
   model-signing-unit-tests:
     name: Run unit tests for signing