Auto merge of #19585 - tigercosmos:b1, r=KiChjang

remove unused `self` in canvas_paint_thread

<!-- Please describe your changes on the following line: -->
```
Compiling canvas v0.0.1 (file:///Users/tigercosmos/servo/components/canvas)
warning: unused import: `self`
  --> components/canvas/canvas_paint_thread.rs:14:24
   |
14 | use ipc_channel::ipc::{self, IpcSender, IpcReceiver};
   |                        ^^^^
   |
   = note: #[warn(unused_imports)] on by default
```

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- [X] `./mach test-tidy` does not report any errors
- [ ] 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::{IpcSender, IpcReceiver};
 use num_traits::ToPrimitive;
 use std::borrow::ToOwned;
 use std::mem;