Invalid module order

Module order is incorrect for compression module. For example, if using `ngx_http_sub_module`, string is not replaced because it it tries to replace content when it is already compressed.

For inspiration you can check  

https://github.com/google/ngx_brotli/blob/a71f9312c2deb28875acc7bacfdd5695a111aa53/filter/config#L70-L85