Releases: more GC assert coverage

RELEASES.rst

@@ -2481,6 +2481,8 @@ Planned
 * Avoid a harmless GC refcount assert when abandoning an object's array part
   (GH-1408)
 
+* More assertion coverage for GC (GH-1411)
+
 * Fix a garbage collection bug where a finalizer triggered by mark-and-sweep
   could cause a recursive entry into mark-and-sweep (leading to memory unsafe
   behavior) if the voluntary GC trigger counter dropped to zero during