disable_compression doesn't seem to be working

#### Overview of the Issue
I have two consul servers configured more or less like this (different IP addresses)

`{
"datacenter": "test",
"data_dir": "/opt/consul",
"encrypt": "####",
"client_addr": "10.30.54.161",
"addresses": {
"http": "0.0.0.0"
},
"server": true,
"bootstrap_expect": 2,
"ui": true,
"bind_addr": "10.30.54.161",
"dns_config": {
"disable_compression": true
}

}`

#### Reproduction Steps
Setup Consul with disable_compression, the response from a SRV DNS query is still compressed.
This actually crashes Go, which doesn't allow compressed SRV records.

### Operating system and Environment details
Consul v1.5.2
Ubuntu Server 18.04.02 LTS

No source files or tests are named. Start by reproducing the SRV DNS query with Consul v1.5.2 and dns_config.disable_compression enabled on Ubuntu 18.04. Done means the SRV response is uncompressed and no longer triggers the reported Go crash.

Written by the indexing model from the issue text.