Enable and fix some more clippy lints (#7426)

One can never have too many lints

crates/eframe/src/epi.rs

@@ -893,16 +893,15 @@ pub trait Storage {
 #[cfg(feature = "ron")]
 pub fn get_value<T: serde::de::DeserializeOwned>(storage: &dyn Storage, key: &str) -> Option<T> {
     profiling::function_scope!(key);
-    storage
-        .get_string(key)
-        .and_then(|value| match ron::from_str(&value) {
-            Ok(value) => Some(value),
-            Err(err) => {
-                // This happens on when we break the format, e.g. when updating egui.
-                log::debug!("Failed to decode RON: {err}");
-                None
-            }
-        })
+    let value = storage.get_string(key)?;
+    match ron::from_str(&value) {
+        Ok(value) => Some(value),
+        Err(err) => {
+            // This happens on when we break the format, e.g. when updating egui.
+            log::debug!("Failed to decode RON: {err}");
+            None
+        }
+    }
 }
 
 /// Serialize the given value as [RON](https://github.com/ron-rs/ron) and store with the given key.