Suppress unexpected warning messages when running .tst files in test/ dir (bug #64123) * bug-53579.tst: Temporarily disable 'Octave:global-local-conflict' warning. * leftdiv.tst: Change 4 %!assert tests to %!warning tests looking for 'Octave:singular-matrix' warning. * parser.tst: Temporarily disable 'Octave:colon-nonscalar-argument' warning. * range.tst: Temporarily disable 'Octave:colon-complex-argument' warning. * struct.tst: Temporarily disable 'Octave:empty-index' warning.

--- a/test/struct.tst	Sun Apr 30 16:55:20 2023 +0200
+++ b/test/struct.tst	Sun Apr 30 15:44:32 2023 -0700
@@ -247,6 +247,7 @@
 %! y = x;
 %! assert (! isempty (y));
 %! assert (y, x);
+%! warning ('off', 'Octave:empty-index', 'local');
 %! z = x();
 %! assert (! isempty (z));
 %! assert (z, x);