Auto merge of #19609 - tigercosmos:q1, r=emilio

remove unsued IpcReceiver

<!-- Please describe your changes on the following line: -->
```
warning: unused import: `IpcReceiver`
  --> components/canvas/canvas_paint_thread.rs:14:41
   |
14 | use ipc_channel::ipc::{self, IpcSender, IpcReceiver};
   |                                         ^^^^^^^^^^^
   |
   = note: #[warn(unused_imports)] on by default
```

recently I have done similar commits for three times
Shall we merge #19573?

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- [ ] These changes fix #__ (github issue number if applicable).

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components/canvas/canvas_paint_thread.rs

@@ -11,7 +11,7 @@ use azure::azure_hl::SurfacePattern;
 use canvas_traits::canvas::*;
 use cssparser::RGBA;
 use euclid::{Transform2D, Point2D, Vector2D, Rect, Size2D};
-use ipc_channel::ipc::{self, IpcSender, IpcReceiver};
+use ipc_channel::ipc::{self, IpcSender};
 use num_traits::ToPrimitive;
 use std::borrow::ToOwned;
 use std::mem;