[BugFix] Preserve spec decoding uniform decode when scheduling (#29759)

Signed-off-by: Nick Hill <nhill@redhat.com>

tests/v1/e2e/test_spec_decode.py

@@ -191,8 +191,8 @@ def test_suffix_decoding_acceptance(
     # Expect the acceptance rate to improve.
     assert first_accept_rate < last_accept_rate
 
-    # Heuristic: expect at least 85% acceptance rate at the end.
-    assert last_accept_rate > 0.85
+    # Heuristic: expect at least 82.5% acceptance rate at the end.
+    assert last_accept_rate > 0.825
 
     del spec_llm
     torch.cuda.empty_cache()