Does not compile with Nginx 1.21.1

Compiler complains with:

```
nginx_ajp_module/ngx_http_ajp.c:140:29: Fehler: »ngx_http_request_t« {alias »struct ngx_http_request_s«} hat kein Element namens »space_in_uri«; meinten Sie »plus_in_uri«?
     if (r->quoted_uri || r->space_in_uri || r->internal) {
                             ^~~~~~~~~~~~
                             plus_in_uri
```
