Omit failing test on 32-bit machines.

This test is intended to verify that 64-bit
machines can handle parsing dates in 2039 and
beyond, and fails on 32-bit machines. It is now
omitted when run on a 32-bit machine to eliminate
an expected failure.

tests-clar/date/date.c

@@ -4,10 +4,12 @@
 
 void test_date_date__overflow(void)
 {
+#ifdef __LP64__
    git_time_t d2038, d2039;
 
-   /* This fails on a 32-bit machine. */
+   /* This is expected to fail on a 32-bit machine. */
    cl_git_pass(git__date_parse(&d2038, "2038-1-1"));
    cl_git_pass(git__date_parse(&d2039, "2039-1-1"));
    cl_assert(d2038 < d2039);
+#endif
 }