Auto merge of #296 - waywardmonkeys:clippy-core-foundation-missing-default, r=jdm

clippy: Add missing Default impls.

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core-foundation/src/attributed_string.rs

@@ -77,3 +77,9 @@ impl CFMutableAttributedString {
         }
     }
 }
+
+impl Default for CFMutableAttributedString {
+    fn default() -> Self {
+        Self::new()
+    }
+}

core-foundation/src/dictionary.rs

@@ -272,6 +272,12 @@ impl<K, V> CFMutableDictionary<K, V> {
     }
 }
 
+impl<K, V> Default for CFMutableDictionary<K, V> {
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
 impl<'a, K, V> From<&'a CFDictionary<K, V>> for CFMutableDictionary<K, V> {
     /// Creates a new mutable dictionary with the key-value pairs from another dictionary.
     /// The capacity of the new mutable dictionary is not limited.

core-foundation/src/uuid.rs

@@ -38,6 +38,12 @@ impl CFUUID {
     }
 }
 
+impl Default for CFUUID {
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
 #[cfg(feature = "with-uuid")]
 impl Into<Uuid> for CFUUID {
     fn into(self) -> Uuid {