message: release-process: Specify remote name in "git fetch"
  Avoids "does not appear to be a git repository" error.
  Fixes
diff: @@ -97,7 +97,7 @@ Checkout the Bitcoin Core version you'd like to build:
  pushd ./bitcoin
  SIGNER='(your builder key, ie bluematt, sipa, etc)'
  VERSION='(new version without v-prefix, e.g. 0.20.0)'
  -git fetch "v${VERSION}"
  +git fetch origin "v${VERSION}"
  git checkout "v${VERSION}"
  popd
  ```
  