Rust: Fix compilation errors in example code.

Author: geoffw0

rust/ql/src/queries/security/CWE-117/LogInjectionBad.rs

@@ -3,11 +3,11 @@ use log::info;
 
 fn main() {
     env_logger::init();
-    
+
     // Get username from command line arguments
     let args: Vec<String> = env::args().collect();
-    let username = args.get(1).unwrap_or(&String::from("Guest"));
-    
+    let username = args.get(1).unwrap_or(&String::from("Guest")).clone();
+
     // BAD: log message constructed with unsanitized user input
     info!("User login attempt: {}", username);
-}
+}

rust/ql/src/queries/security/CWE-117/LogInjectionGood.rs

@@ -8,12 +8,12 @@ fn sanitize_for_logging(input: &str) -> String {
 
 fn main() {
     env_logger::init();
-    
+
     // Get username from command line arguments
     let args: Vec<String> = env::args().collect();
-    let username = args.get(1).unwrap_or(&String::from("Guest"));
-    
+    let username = args.get(1).unwrap_or(&String::from("Guest")).clone();
+
     // GOOD: log message constructed with sanitized user input
-    let sanitized_username = sanitize_for_logging(username);
+    let sanitized_username = sanitize_for_logging(username.as_str());
     info!("User login attempt: {}", sanitized_username);
-}
+}