feat: Bump lib/pq from 1.10.4 to 1.10.7

[aletournel]

Hi @cyrilgdn ,

First, thanks for implementing this Terraform provider for PostgreSQL.

So here is a little bit of context first: at my company, we use a proxy to connect to our PostgreSQL servers and use the host in SNI to route the requests to the correct PostgreSQL server.

Unfortunately, the pq lib in version 1.10.4 doesn't specify a host when using SNI. But they did a fix six months ago for that (see lib/pq#1088) and released it in the 1.10.7 version. So I forked the provider, made this change and tested it on our deployment pipeline. It worked and made communication with the PostgreSQL servers through the proxy possible.

So this is why I created this PR to update pq lib to 1.10.7 from 1.10.4, and it would be fantastic if you could approve it so we can use your provider and not the fork I did.

Thanks in advance, and thanks again for all your work on this provider

[cyrilgdn]

Thanks for the (well explained) PR 👍