Try this

Author: anomiex

.github/workflows/test.yml

@@ -301,6 +301,8 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        include: ${{ fromJson( '[]' ) }}
+        foo: []
     steps:
-      - run: true
+      - env:
+          FOO: ${{ matrix.foo }}
+        run: echo "$FOO"