feat: add some benches to compare with linicon

benches/simple_lookup.rs

@@ -0,0 +1,17 @@
+use criterion::{black_box, criterion_group, criterion_main, Criterion};
+use freedesktop_icons::lookup;
+
+pub fn simple_lookup(c: &mut Criterion) {
+    c.bench_function("lookup firefox", |b| {
+        b.iter(|| lookup("firefox").find_one())
+    });
+}
+
+pub fn simple_lookup_linicon(c: &mut Criterion) {
+    c.bench_function("lookup firefox linicon", |b| {
+        b.iter(|| linicon::lookup_icon("firefox").next().unwrap().unwrap())
+    });
+}
+
+criterion_group!(benches, simple_lookup, simple_lookup_linicon);
+criterion_main!(benches);