avoid cloning the source code (#8556)

### Description

avoid unnecessary clone of source code

### Testing Instructions

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  Give a quick description of steps to test your changes.
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crates/turbopack-ecmascript/src/parse.rs

@@ -278,7 +278,7 @@ async fn parse_content(
     let mut result = WrapFuture::new(
         async {
             let file_name = FileName::Custom(ident.to_string());
-            let fm = source_map.new_source_file(file_name.clone(), string.clone());
+            let fm = source_map.new_source_file(file_name.clone(), string);
 
             let comments = SwcComments::default();
 
@@ -419,7 +419,7 @@ async fn parse_content(
                 } else {
                     None
                 };
-                let messages = Some(messages.unwrap_or_else(|| vec![string.into()]));
+                let messages = Some(messages.unwrap_or_else(|| vec![fm.src.clone().into()]));
                 return Ok(ParseResult::Unparseable { messages });
             }