This removes feature flags that were unused. FEATURE_SOCKET_EAP and FEATURE_DNS_SYNC were set for all frameworks, so unneeded. The other feature flags were only used in elif of FEATURE_SOCKET_EAP and FEATURE_DNS_SYNC, so also unneeded.
After removing these, DnsAbstractions.cs seemed to be an unneeded abstraction at first, but then I noticed that .NET 6+ supports a cancellationToken on GetHostAddressesAsync, so I kept DnsAbstractions.cs to pass this through (I could do a separate PR for this if you want).
This removes feature flags that were unused. FEATURE_SOCKET_EAP and FEATURE_DNS_SYNC were set for all frameworks, so unneeded. The other feature flags were only used in elif of FEATURE_SOCKET_EAP and FEATURE_DNS_SYNC, so also unneeded.
After removing these, DnsAbstractions.cs seemed to be an unneeded abstraction at first, but then I noticed that .NET 6+ supports a cancellationToken on GetHostAddressesAsync, so I kept DnsAbstractions.cs to pass this through (I could do a separate PR for this if you want).