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/egui_demo_lib/src/easy_mark/easy_mark_editor.rs

@@ -1,4 +1,6 @@
-use egui::{text::CCursorRange, *};
+use egui::{
+    text::CCursorRange, Key, KeyboardShortcut, Modifiers, ScrollArea, TextBuffer, TextEdit, Ui,
+};
 
 #[cfg_attr(feature = "serde", derive(serde::Deserialize, serde::Serialize))]
 #[cfg_attr(feature = "serde", serde(default))]

crates/egui_demo_lib/src/easy_mark/easy_mark_viewer.rs

@@ -1,5 +1,8 @@
 use super::easy_mark_parser as easy_mark;
-use egui::*;
+use egui::{
+    vec2, Align, Align2, Hyperlink, Layout, Response, RichText, Sense, Separator, Shape, TextStyle,
+    Ui,
+};
 
 /// Parse and display a VERY simple and small subset of Markdown.
 pub fn easy_mark(ui: &mut Ui, easy_mark: &str) {