v0.3.0

• Add explicit .NET 8 target framework
• Removed .NET Core 3.1 and .NET 5 target frameworks
• Updated dependencies
• More and improved doc comments.
• Fix callback-based NetUtility.ResolveAsync functions never running their callback. (bug introduced in 0.1.0)
• Default MTU for IPv4 has been dropped to 508 to avoid issues for certain people.
• A separate MTU value is now used for IPv6, as it permits a higher default. You can set it with NetPeerConfiguration.MaximumTransmissionUnitV6
• Fixed MTU expansion not setting internal state correctly and spamming network packets.
• Fixed NetPeerConfiguration.ExpandMTUFailAttempts not being respected completely.
• The new NetPeerMetrics allows exporting metrics about the library to System.Diagnostics.Metrics.
• Internal code cleanup.