ci: Execute newt test with super powers

This is required by latest MacOS runners (see [1]) and
doesn't affect Linux. For simplicity keep same job for all.

[1] actions/runner-images#10924

Author: sjanc

.github/workflows/newt_test_all.yml

@@ -62,4 +62,4 @@ jobs:
       - name: newt test all
         run: |
              cd build
-             newt test all
+             sudo `which newt` test all