Merge #15073: docs: Botbot.me (IRC logs) not available anymore

b60ac00d2 Botbot.me (IRC logs) not available anymore (Antti Majakivi)

Pull request description:

  Remove botbot.me link as it's [not available anymore](https://lincolnloop.com/blog/saying-goodbye-botbotme/) and add two other IRC history log sources for #bitcoin-core-dev, http://www.erisian.com.au/bitcoin-core-dev/ and http://gnusha.org/bitcoin-core-dev/.

Tree-SHA512: 025477b33542c8b91fa99eec7f5cdff043da4bf11e0f8ceba8175fe3ca171ba66a66040673e487a85babe790514a1c8f9b5ce8a31013c01befb050272b6ca33a

CONTRIBUTING.md

@@ -25,7 +25,8 @@ Most communication about Bitcoin Core development happens on IRC, in the
 #bitcoin-core-dev channel on Freenode. The easiest way to participate on IRC is
 with the web client, [webchat.freenode.net](https://webchat.freenode.net/). Chat
 history logs can be found
-on [botbot.me](https://botbot.me/freenode/bitcoin-core-dev/).
+on [http://www.erisian.com.au/bitcoin-core-dev/](http://www.erisian.com.au/bitcoin-core-dev/)
+and [http://gnusha.org/bitcoin-core-dev/](http://gnusha.org/bitcoin-core-dev/).
 
 Discussion about code base improvements happens in GitHub issues and on pull
 requests.