add null check for sym_new(ctx) in make_bottom

Author: A0su

Python/optimizer_symbols.c

@@ -1684,6 +1684,9 @@ static JitOptSymbol *
 make_bottom(JitOptContext *ctx)
 {
     JitOptSymbol *sym = sym_new(ctx);
+    if (res == NULL) {
+        return out_of_space_ref(ctx);
+    }
     sym->tag = JIT_SYM_BOTTOM_TAG;
     return sym;
 }