[BUGFIX] Fix flaky test #19197 by avoiding case that 0.45 mapped to 0.5

tests/python/unittest/test_contrib_intgemm.py

@@ -53,7 +53,8 @@ def test_contrib_intgemm_prepare_data():
         scaled = m * 127.0 / max_quant
         # Rounding 0.5 can go up or down.  Move values away from 0.5.
         too_close = mx.nd.abs(mx.nd.round(scaled) - scaled) > 0.45
-        m += max_quant / 127.0 * 0.05 * too_close
+        # Add 0.2 in scaled space so (0.45, 0.55) maps to (0.65, 0.75) which will round consistently.
+        m += max_quant / 127.0 * 0.2 * too_close
 
         # Reference: scale and round
         ref = mx.nd.round(m * 127.0 / max_quant)