src: fix new linting warnings

Signed-off-by: Luca BRUNO <[email protected]>

Author: lucab

src/registry.rs

@@ -183,8 +183,8 @@ impl RegistryCore {
 
         // Write out MetricFamilies sorted by their name.
         mf_by_name
-            .into_iter()
-            .map(|(_, mut m)| {
+            .into_values()
+            .map(|mut m| {
                 // Add registry namespace prefix, if any.
                 if let Some(ref namespace) = self.prefix {
                     let prefixed = format!("{}_{}", namespace, m.get_name());

static-metric/src/auto_flush_builder.rs

@@ -714,7 +714,6 @@ impl<'a> MetricBuilderContext<'a> {
                         })#local_suffix_call,
                     }
                 } else {
-                    let prev_labels_ident = prev_labels_ident;
                     quote! {
                         #name: #member_type::from(
                             #(

static-metric/src/builder.rs

@@ -300,7 +300,6 @@ impl<'a> MetricBuilderContext<'a> {
                         })#local_suffix_call,
                     }
                 } else {
-                    let prev_labels_ident = prev_labels_ident;
                     quote! {
                         #name: #member_type::from(
                             #(