`kctrl package repository` should have a pause command

**Describe the problem/challenge you have**
Currently the only way to pause a package repository is by manually editing the package repository and adding paused: true in the specs.

**Describe the solution you'd like**
Add `kctrl package repository pause` command.

**Anything else you would like to add:**
We already have a `kctrl package repository kick` command which basically does pause->unpause a package repository, so we already have the pause logic, we just need to add a new command that uses it.

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