LibWeb: Remove double comma in FrameLoader debug logging

Author: https://github.com/IdanHo
Commit: https://github.com/SerenityOS/serenity/commit/37903db2b4e
Pull-request: https://github.com/SerenityOS/serenity/pull/6876

Userland/Libraries/LibWeb/Loader/FrameLoader.cpp

@@ -236,7 +236,7 @@ void FrameLoader::resource_did_load()
         return;
     }
 
-    dbgln("I believe this content has MIME type '{}', , encoding '{}'", resource()->mime_type(), resource()->encoding());
+    dbgln("I believe this content has MIME type '{}', encoding '{}'", resource()->mime_type(), resource()->encoding());
 
     auto document = DOM::Document::create();
     document->set_url(url);