[Heimdal-source-changes] [heimdal/heimdal] e3dbc8: appveyor: Install zstd before other pkgs

[Nico Williams]

  Branch: refs/heads/master
  Home:   https://github.com/heimdal/heimdal
  Commit: e3dbc89f8fb6dd0a3a07caee7f752dc2bec3b6d9
      https://github.com/heimdal/heimdal/commit/e3dbc89f8fb6dd0a3a07caee7f752dc2bec3b6d9
  Author: Nicolas Williams <nico at twosigma.com>
  Date:   2020-05-25 (Mon, 25 May 2020)

  Changed paths:
    M appveyor.yml

  Log Message:
  -----------
  appveyor: Install zstd before other pkgs

Some pacman packages are now being compressed with the ZST algorithm,
but pacman can't handle that unless we first install `zstd`.  This
commit does that.