Fix clippy warnings in aws-smithy-legacy-http

Author: Fahad Zubair

rust-runtime/aws-smithy-legacy-http/src/endpoint.rs

@@ -32,7 +32,7 @@ pub fn apply_endpoint(
         .map(|auth| auth.as_str())
         .unwrap_or("");
     let authority = if !prefix.is_empty() {
-        Cow::Owned(format!("{}{}", prefix, authority))
+        Cow::Owned(format!("{prefix}{authority}"))
     } else {
         Cow::Borrowed(authority)
     };
@@ -66,6 +66,6 @@ fn merge_paths<'a>(endpoint: &'a http_1x::Uri, uri: &'a http_1x::Uri) -> Cow<'a,
         let uri_path_no_slash = uri_path_and_query
             .strip_prefix('/')
             .unwrap_or(uri_path_and_query);
-        Cow::Owned(format!("{}/{}", ep_no_slash, uri_path_no_slash))
+        Cow::Owned(format!("{ep_no_slash}/{uri_path_no_slash}"))
     }
 }

rust-runtime/aws-smithy-legacy-http/src/header.rs

@@ -64,7 +64,7 @@ pub fn many_dates<'a>(
         let mut header = header;
         while !header.is_empty() {
             let (v, next) = DateTime::read(header, format, ',').map_err(|err| {
-                ParseError::new(format!("header could not be parsed as date: {}", err))
+                ParseError::new(format!("header could not be parsed as date: {err}"))
             })?;
             out.push(v);
             header = next;

rust-runtime/aws-smithy-legacy-http/src/query_writer.rs

@@ -162,7 +162,7 @@ mod test {
         }
 
         if !problematic_chars.is_empty() {
-            panic!("we got some bad bytes here: {:#?}", problematic_chars)
+            panic!("we got some bad bytes here: {problematic_chars:#?}")
         }
     }