Remove noisy assert from Task (#86445)

Author: stephentoub

src/libraries/System.Private.CoreLib/src/System/Threading/Tasks/Task.cs

@@ -2544,10 +2544,10 @@ internal void UnsafeSetContinuationForAwait(IAsyncStateMachineBox stateMachineBo
 
             // This code path doesn't emit all expected TPL-related events, such as for continuations.
             // It's expected that all callers check whether events are enabled before calling this function,
-            // and only call it if they're not, so we assert. However, as events can be dynamically turned
-            // on and off, it's possible this assert could fire even when used correctly.  If it becomes
-            // noisy, it can be deleted.
-            Debug.Assert(!TplEventSource.Log.IsEnabled());
+            // and only call it if they're not. However, as events can be dynamically turned
+            // on and off, it's possible this assert could fire even when used correctly. Do not call this
+            // method unless you've checked that TplEventSource.Log.IsEnabled() is false (if it becomes true after
+            // the check, that's fine, and a natural race condition that's unavoidable).
 
             // If the caller wants to continue on the current context/scheduler and there is one,
             // fall back to using the state machine's delegate.