Rolling back PR #305 for Mullvad configs, while keeping switch from URLs to IP addresses

[sntyj]

Breaking change

This is not a breaking change, it should fix it. 

Proposed change

I replaced block-outside-dns as this is a Windows specific option, that doesn't have a place with this container: 

https://openvpn.net/community-resources/reference-manual-for-openvpn-2-5/

I replaced the 'service' parameter as it is a deprecated option in OpenVPN from what I can tell:

https://community.openvpn.net/openvpn/wiki/DeprecatedOptions#Windows:openvpn-legacy-serviceStatus:Removed

I kept the switch from URLs to IP addresses, because I think that is a valid change that could help alleviate issues if DNS doesn't resolve on the client for some reason. 

Type of change

• Bugfix (non-breaking change which fixes an issue)
• New provider (thank you!)
• Updated provider (thank you!)
• New feature (which adds functionality to a provider script/repo usage)
• Breaking change (fix/feature causing existing functionality to break)

Additional information

• This PR fixes or closes issue: fixes #311

Checklist

• The code change is tested and works locally. (I am running this version of the configuration currently)
• There is no commented out code in this PR.

If user exposed functionality or configuration variables are added/changed:

• Documentation added/updated