[glib/wip/pwithnall/ci-fixes] tests: Add more debug output to converter-stream test

[Philip Withnall <pwithnall src gnome org>]

commit 54ee8e54141df2aae476d07930dc3eaa1c41f9bf
Author: Philip Withnall <pwithnall endlessos org>
Date:   Fri Mar 4 19:51:17 2022 +0000

    tests: Add more debug output to converter-stream test
    
    It’s periodically failing on FreeBSD and I can’t reproduce the failure
    locally nor work out what it is from the logs:
    ```
    Bail out! GLib-GIO:ERROR:../gio/tests/converter-stream.c:1041:test_converter_pollable: assertion failed 
(res != -1): (-1 != -1)
    stderr:
    **
    GLib-GIO:ERROR:../gio/tests/converter-stream.c:1041:test_converter_pollable: assertion failed (res != 
-1): (-1 != -1)
    ```
    
    Add some more debug output to get the value of `error`, in the hope that
    will provide some insight.
    
    See: https://gitlab.gnome.org/GNOME/glib/-/jobs/1866486
    
    Signed-off-by: Philip Withnall <pwithnall endlessos org>

 gio/tests/converter-stream.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)
---
diff --git a/gio/tests/converter-stream.c b/gio/tests/converter-stream.c
index 8c4731590..b23436d8f 100644
--- a/gio/tests/converter-stream.c
+++ b/gio/tests/converter-stream.c
@@ -1038,7 +1038,10 @@ test_converter_pollable (void)
 
       /* After closing the write end, we can't get WOULD_BLOCK any more */
       if (!socket_out)
-       g_assert_cmpint (res, !=, -1);
+        {
+          g_assert_no_error (error);
+          g_assert_cmpint (res, !=, -1);
+        }
 
       if (res == -1)
        {