Create release for `polkadot-stable2512`

[Niederb]

Polkadot will probably release polkadot-stable2512 at the beginning of January.

[clangenb]

Moinsen,

stable2512 has been released. May I ask when you expect to be working on this? (no hurry, just for my own planning) :)

[haerdib]

Hey @clangenb we will release finish this by the end of next week latest. Hope that's alright for you :)

[clangenb]

Awesome ❤️