Feature Request: `vitess/vtctldclient` container image

[runewake2]

Feature Description

vtctldclient has been introduced to provide stronger typing over vtctlclient however a containerized copy of the vtctldclient is not currently being published with the Vitess docker images. I'm proposing adding a new container with the vtctldclient binary similar to the already published vitess/vtctlclient image.

Use Case(s)

• vtctldclient currently is installed by a build of the Vitess source code, this container would provide a way to use this tool without requiring that. That introduces some uses specifically for building out vitess testing environments where vtctldclient operations would be handy.
• It also enables further replacing of the old vtctlclient uses with the updated vtctldclient tool.