Remove wildcard imports (#5018)

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I removed (I hope so) all wildcard imports I found.

For me on my pc this improved the build time:
- for egui -5s
- for eframe -12s

* [x] I have followed the instructions in the PR template

crates/epaint/src/bezier.rs

@@ -4,7 +4,7 @@
 use std::ops::Range;
 
 use crate::{shape::Shape, Color32, PathShape, PathStroke};
-use emath::*;
+use emath::{Pos2, Rect, RectTransform};
 
 // ----------------------------------------------------------------------------
 
@@ -762,6 +762,8 @@ fn cubic_for_each_local_extremum<F: FnMut(f32)>(p0: f32, p1: f32, p2: f32, p3: f
 
 #[cfg(test)]
 mod tests {
+    use emath::pos2;
+
     use super::*;
 
     #[test]