Fix false positive in WorkQueue.addLast (#2968)

Fixes #2937

Author: dkhalanskyjb

kotlinx-coroutines-debug/src/CoroutinesBlockHoundIntegration.kt

@@ -19,6 +19,7 @@ public class CoroutinesBlockHoundIntegration : BlockHoundIntegration {
         allowServiceLoaderInvocationsOnInit()
         allowBlockingCallsInReflectionImpl()
         allowBlockingCallsInDebugProbes()
+        allowBlockingCallsInWorkQueue()
         // Stacktrace recovery cache is guarded by lock
         allowBlockingCallsInside("kotlinx.coroutines.internal.ExceptionsConstructorKt", "tryCopyException")
         /* The predicates that define that BlockHound should only report blocking calls from threads that are part of
@@ -62,6 +63,14 @@ public class CoroutinesBlockHoundIntegration : BlockHoundIntegration {
         }
     }
 
+    /**
+     * Allow blocking calls inside [kotlinx.coroutines.scheduling.WorkQueue]
+     */
+    private fun BlockHound.Builder.allowBlockingCallsInWorkQueue() {
+        /** uses [Thread.yield] in a benign way. */
+        allowBlockingCallsInside("kotlinx.coroutines.scheduling.WorkQueue", "addLast")
+    }
+
     /**
      * Allows blocking inside [kotlinx.coroutines.internal.ThreadSafeHeap].
      */