Merge bitcoin/bitcoin#22970: doc: Update snap release process for new versioning scheme

fad8606 doc: Update snap release process for new versioning scheme (MarcoFalke)

Pull request description:

ACKs for top commit:
  jarolrod:
    ACK fad8606
  fanquake:
    ACK fad8606 - moving these instructions to the packaging repo.

Tree-SHA512: 80a9d1484a6544e44a7e57967a62d6e3084efe946de40ac5f0ad0aeb79399d578a7b690186b33d394402d383715741203ebd09ff3f376a5f657045ed96f273e7

Author: fanquake

doc/release-process.md

@@ -271,26 +271,7 @@ cat "$VERSION"/*/all.SHA256SUMS.asc > SHA256SUMS.asc
 
       - Push the flatpak to flathub, e.g. https://github.com/flathub/org.bitcoincore.bitcoin-qt/pull/2
 
-      - Push the latest version to master (if applicable), e.g. https://github.com/bitcoin-core/packaging/pull/32
-
-      - Create a new branch for the major release "0.xx" from master (used to build the snap package) and request the
-        track (if applicable), e.g. https://forum.snapcraft.io/t/track-request-for-bitcoin-core-snap/10112/7
-
-      - Notify MarcoFalke so that he can start building the snap package
-
-        - https://code.launchpad.net/~bitcoin-core/bitcoin-core-snap/+git/packaging (Click "Import Now" to fetch the branch)
-        - https://code.launchpad.net/~bitcoin-core/bitcoin-core-snap/+git/packaging/+ref/0.xx (Click "Create snap package")
-        - Name it "bitcoin-core-snap-0.xx"
-        - Leave owner and series as-is
-        - Select architectures that are compiled via guix
-        - Leave "automatically build when branch changes" unticked
-        - Tick "automatically upload to store"
-        - Put "bitcoin-core" in the registered store package name field
-        - Tick the "edge" box
-        - Put "0.xx" in the track field
-        - Click "create snap package"
-        - Click "Request builds" for every new release on this branch (after updating the snapcraft.yml in the branch to reflect the latest guix results)
-        - Promote release on https://snapcraft.io/bitcoin-core/releases if it passes sanity checks
+      - Push the snap, see https://github.com/bitcoin-core/packaging/blob/master/snap/build.md
 
   - This repo