testsuite: Show exit code of GHCi tests on failure
With 3394a7cd we started showing the exit code when a test fails with an unexpected exit code. This commit does the same when a GHCi test fails with an exit code mismatch.
With 3394a7cd we started showing the exit code when a test fails with an unexpected exit code. This commit does the same when a GHCi test fails with an exit code mismatch.