promote-charm action fails with resources

[samuelallan72]

Bug Description

This was observed and reported here: canonical/charm-prometheus-libvirt-exporter#58

It appears that the promote action does not handle resources, or at least fails if it tries promoting a charm with resources to a new channel. I'm unsure if the channel in the original bug report was a new channel or not.

To Reproduce

1. publish a charm that has resources to edge channel
2. use this action to promote the charm to candidate

Environment

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Relevant log output

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Additional context

No response