ci: fix ptr_arithmetic_test.v

vlib/v/tests/ptr_arithmetic_test.v

@@ -20,20 +20,20 @@ fn test_ptr_arithmetic() {
 
 fn test_ptr_arithmetic_over_byteptr() {
 	// byteptr, voidptr, charptr are handled differently
-	mut q := byteptr(10)
+	mut q := &byte(10)
 	unsafe {
 		q -= 2
 		q = q + 1
 	}
-	assert q == byteptr(9)
+	assert u64(q) == u64(&byte(9))
 	s := unsafe { q - 1 }
-	assert s == byteptr(8)
+	assert u64(s) == u64(&byte(8))
 	unsafe {
 		q++
 		q++
 		q--
 	}
-	assert q == byteptr(10)
+	assert u64(q) == u64(&byte(10))
 }
 
 struct Abc {