doc/turtorial/kubernetes: fix invalid user commands

[yujunz]

No description provided.

[yujunz]

This PR solves the following errors in user command

$ cue ls ./...
command.ls.task.print: alias values not allowed in this position:
    ./ls_tool.cue:8:3

$ cue dump ./...
command.dump.task.print.text: invalid string argument: incomplete value:
    ./dump_tool.cue:6:8
    ./dump_tool.cue:8:3
    ./dump_tool.cue:8:9

[myitcv]

Thanks - noting #824, in particular my desire that we should be able to re-run this tutorial exactly as the user might run it.