Remove WNOHANG from regression test

regression/apps/hello_world/hello_world.S

@@ -0,0 +1,28 @@
+# SPDX-License-Identifier: MPL-2.0
+
+.global _start
+
+.section .text
+_start:
+    call    print_message
+    call    print_message
+    call    print_message
+    mov     $60, %rax               # syscall number of exit
+    mov     $0, %rdi                # exit code
+    syscall     
+get_pid: 
+    mov     $39, %rax
+    syscall
+    ret
+print_message:
+    mov     $1, %rax                # syscall number of write
+    mov     $1, %rdi                # stdout
+    mov     $message, %rsi          # address of message         
+    mov     $message_end, %rdx
+    sub     %rsi, %rdx              # calculate message len
+    syscall
+    ret
+.section .rodata            
+message:
+    .ascii  "Hello, world\n"
+message_end: