Use the wapp.h header in tests

tests/arena/test_arena.c

@@ -1,8 +1,5 @@
 #include "test_arena.h"
-#include "aliases.h"
-#include "mem_arena.h"
-#include "misc_utils.h"
-#include "tester.h"
+#include "wapp.h"
 #include <stdbool.h>
 #include <stdlib.h>
 

tests/arena/test_arena.h

@@ -1,7 +1,7 @@
 #ifndef TEST_ARENA_H
 #define TEST_ARENA_H
 
-#include "tester.h"
+#include "wapp.h"
 
 #ifdef __cplusplus
 BEGIN_C_LINKAGE