zephyr/main: Don't unconditionally dump stats on each GC.

This was a debug output for initial porting, breaks tests.

zephyr/main.c

@@ -126,7 +126,7 @@ void gc_collect(void) {
     gc_collect_start();
     gc_collect_root(&dummy, ((mp_uint_t)stack_top - (mp_uint_t)&dummy) / sizeof(mp_uint_t));
     gc_collect_end();
-    gc_dump_info();
+    //gc_dump_info();
 }
 
 mp_lexer_t *mp_lexer_new_from_file(const char *filename) {