Question about PRs (I have a new function to contribute)

Hey folks!

I make regular use of this extension and have made a function `expand_cidr()` that takes in an IP address (network or bare) and returns the expanded IPs from the CIDR in a list/array. Handles IPv4 & v6.

I'm curious if (a) y'all accept PRs and (b) if so, what should I do to ensure the least amount of work on your end?

A short example:

```
🦆>SELECT UNNEST(expand_cidr('192.168.1.0/32'::INET)) ip;
┌─────────────┐
│ ip │
│ inet │
├─────────────┤
│ 192.168.1.0 │
└─────────────┘
🦆>SELECT UNNEST(expand_cidr('192.168.1.0/30'::INET)) ip;
┌─────────────┐
│ ip │
│ inet │
├─────────────┤
│ 192.168.1.0 │
│ 192.168.1.1 │
│ 192.168.1.2 │
│ 192.168.1.3 │
└─────────────┘
🦆>FROM (SELECT UNNEST(expand_cidr('192.168.1.0/16'::INET)) ip) SELECT COUNT(ip);
┌───────────┐
│ count(ip) │
│ int64 │
├───────────┤
│ 65536 │
└───────────┘
🦆>
```

Please ignore this PR: https://github.com/duckdb/duckdb-inet/pull/3

This is the correct PR: https://github.com/duckdb/duckdb-inet/pull/5