.github/workflows/runner.yml: trap(1) to see the testsuite log

Otherwise, 'cat testsuite.log' isn't run, since 'set -e' aborts the
script earlier.

Reviewed-by: "Serge E. Hallyn" <serge@hallyn.com>
Cc: Iker Pedrosa <ipedrosa@redhat.com>
Signed-off-by: Alejandro Colomar <alx@kernel.org>

.github/workflows/runner.yml

@@ -49,8 +49,9 @@ jobs:
       run: |
         set -e
         cd tests
+        trap 'cat testsuite.log' ERR
         sudo ./run_some
-        cat testsuite.log
+        trap - ERR
 
   # Make sure that 'make dist' makes a usable tarball with no missing files
   dist-build: