fix: Adjust sleep test to have more buffer

This test was failing on the Windows CI, with a diff greater than 999 ms (but lower than 1s).
This might be a race condition, or a clock resolution issue, both of which should
be fixed by giving the test an extra 300 ms of legroom.

source/geod24/LocalRest.d

@@ -1676,7 +1676,7 @@ unittest
     assert(current2 - current1 < 200.msecs);
 
     // Make one of the node sleep
-    n1.sleep(1.seconds);
+    n1.sleep(1300.msecs);
     // Make sure our main thread is not suspended,
     // nor is the second node
     assert(2 == n2.call());