Merge branch 'post-11' into post-12

src/interrupts.rs

@@ -92,13 +92,8 @@ extern "x86-interrupt" fn keyboard_interrupt_handler(_stack_frame: &mut Interrup
     }
 }
 
-#[cfg(test)]
-use crate::{serial_print, serial_println};
-
 #[test_case]
 fn test_breakpoint_exception() {
-    serial_print!("test_breakpoint_exception...");
     // invoke a breakpoint exception
     x86_64::instructions::interrupts::int3();
-    serial_println!("[ok]");
 }