Fix some minor clippy lints from the future

crates/epaint/src/lib.rs

@@ -77,6 +77,7 @@ pub use emath;
 pub use ecolor::hex_color;
 
 /// The UV coordinate of a white region of the texture mesh.
+///
 /// The default egui texture has the top-left corner pixel fully white.
 /// You need need use a clamping texture sampler for this to work
 /// (so it doesn't do bilinear blending with bottom right corner).

crates/epaint/src/mesh.rs

@@ -222,7 +222,7 @@ impl Mesh {
     pub fn split_to_u16(self) -> Vec<Mesh16> {
         debug_assert!(self.is_valid());
 
-        const MAX_SIZE: u32 = std::u16::MAX as u32;
+        const MAX_SIZE: u32 = u16::MAX as u32;
 
         if self.vertices.len() <= MAX_SIZE as usize {
             // Common-case optimization:

crates/epaint/src/tessellator.rs

@@ -1537,7 +1537,7 @@ impl Tessellator {
     ///
     /// * `mesh`: the mesh to tessellate.
     /// * `out`: triangles are appended to this.
-    pub fn tessellate_mesh(&mut self, mesh: &Mesh, out: &mut Mesh) {
+    pub fn tessellate_mesh(&self, mesh: &Mesh, out: &mut Mesh) {
         if !mesh.is_valid() {
             debug_assert!(false, "Invalid Mesh in Shape::Mesh");
             return;