Remove tech review markers.

Author: amartini51

stdlib/public/Concurrency/Task.swift

@@ -171,7 +171,6 @@ extension Task {
   /// In both cases, priority elevation helps you prevent a low-priority task
   /// blocking the execution of a high priority task,
   /// which is also known as *priority inversion*.
-  /// ◊TR: Let's revisit the above
   public enum Priority: Int, Comparable {
     // Values must be same as defined by the internal `JobPriority`.
     case userInteractive = 0x21

stdlib/public/Concurrency/TaskGroup.swift

@@ -172,8 +172,6 @@ public func withTaskGroup<ChildTaskResult, GroupResult>(
 ///         group.spawn { throw SomeError() }
 ///         try group.next()
 ///     }
-/// ◊TR: I revised the code listings above compared to what @ktoso suggested
-/// ◊TR: Are they still correct?
 ///
 /// An individual task throws its error
 /// in the corresponding call to `Group.next()`,