Adjust test suites to new `maybe_raise_from_masking_exc()` changes

tests/test_trioisms.py

@@ -119,9 +119,8 @@ def test_acm_embedded_nursery_propagates_enter_err(
             tractor.trionics.maybe_raise_from_masking_exc(
                 tn=tn,
                 unmask_from=(
-                    trio.Cancelled
-                    if unmask_from_canc
-                    else None
+                    (trio.Cancelled,) if unmask_from_canc
+                    else ()
                 ),
             )
         ):
@@ -136,7 +135,6 @@ def test_acm_embedded_nursery_propagates_enter_err(
         with tractor.devx.maybe_open_crash_handler(
             pdb=debug_mode,
         ) as bxerr:
-            if bxerr:
             assert not bxerr.value
 
             async with (
@@ -145,6 +143,7 @@ def test_acm_embedded_nursery_propagates_enter_err(
                 assert not tn.cancel_scope.cancel_called
                 assert 0
 
+        if debug_mode:
             assert (
                 (err := bxerr.value)
                 and