Try to make workflow work in CI

- this is what worked for the xsref first workflow

Author: steppi

.github/workflows/linux.yml

@@ -1,6 +1,6 @@
 name: Linux Tests
 
-on: [ push, pull_request ]
+on [ push, pull_request ]
 
 permissions:
    contents: read  # to fetch code (actions/checkout)