zensical:fix - wrong mime-type when using .mjs

Signed-off-by: squidfunk <martin.donath@squidfunk.com>

crates/zensical-serve/src/http/response/ext.rs

@@ -48,7 +48,7 @@ pub trait ResponseExt: Sized {
         let mime = match path.extension().and_then(|ext| ext.to_str()) {
             Some("html" | "htm") => "text/html; charset=utf-8",
             Some("css") => "text/css",
-            Some("js") => "application/javascript",
+            Some("js" | "mjs") => "application/javascript",
             Some("json") => "application/json",
             Some("png") => "image/png",
             Some("jpg" | "jpeg") => "image/jpeg",