Phrases with spaces break mcmd text search

I think I just did something a little dumb when building the query, and as a result, long phrases cause the query to break.

Find it and fix it.

```
❯ bin/mcmd show logs from server=168a4416-3e6c-4cef-92f3-22a47205ec93 after=2020/08/01 text="authlog" text="bad protocol"
Unhandled exception: syntax error in tsquery: "bad protocol" (PQ::PQError)
from lib/pg/src/pq/connection.cr:214:7 in 'handle_error'
from lib/pg/src/pq/connection.cr:195:9 in 'handle_async_frames'
from lib/pg/src/pq/connection.cr:162:7 in 'read'
from lib/pg/src/pq/connection.cr:157:7 in 'execute_show_logs'
from src/minion/mcmd.cr:205:7 in '__crystal_main'
from ../../../../../../usr/share/crystal/src/crystal/main.cr:105:5 in 'main'
from __libc_start_main
from _start
from ???
```