Merge bitcoin/bitcoin#31976: delete release note fragments for v29

ae92bd8 delete release note fragments for v29 (glozow)

Pull request description:

  Delete release note fragments in preparation for 29.x branch-off.
  Everything here has been copied over to the draft release notes at https://github.com/bitcoin-core/bitcoin-devwiki/wiki/29.0-Release-Notes-draft

ACKs for top commit:
  laanwj:
    ACK ae92bd8
  achow101:
    ACK ae92bd8

Tree-SHA512: adc4d34dfaf1cbbe4c7eddf4d220664e327c450de126040ab8565fc5f20696aaed2d58438aad76e4e343f0abf1b4f28fe1a21d09d957e606403c200858072682

Author: achow101