chore: fix using write!() with a format string that ends in a singl…

…e newline

console-subscriber/tests/support/subscriber.rs

@@ -25,7 +25,7 @@ impl fmt::Display for TestFailure {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         write!(f, "Task validation failed:\n")?;
         for failure in &self.failures {
-            write!(f, " - {failure}\n")?;
+            writeln!(f, " - {failure}")?;
         }
         Ok(())
     }