dnscrypt-proxy plugin ignores do not use IPv6 for DNS

[0xShkk]

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Describe the bug Unchecked the Use IPv6 Servers setting at the plugin's settings, but when using a DNS leak test like the one from https://browserleaks.com/ip I can see IPv6 addresses for the DNS resolvs.

To Reproduce Steps to reproduce the behavior:

1. Install dnscrypt-proxy plugin
2. Disable unbound
3. Use dnscrypt-proxy plugin as system DNS by letting it listen to 0.0.0.0:53
4. Do not check Use IPv6 Servers
5. Check Block IPv6
6. Browse to https://browserleaks.com/ip
7. Try DNS leak
8. See IPv6 addresses for DNS resolvers used

Expected behavior Should not see IPv6 addresses for DNS resolvers.

Environment OPNsense version 24.1.3 (amd64) dnscrypt-proxy plugin version 1.15