Update charmixer/auto-changelog-action action to v1.4

[renovate[bot]]

This PR contains the following updates:

Package	Type	Update	Change
charmixer/auto-changelog-action	action	minor	v1.1 -> v1.4

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Release Notes

charmixer/auto-changelog-action

### [`v1.4`](https://togithub.com/charmixer/auto-changelog-action/releases/tag/v1.4) [Compare Source](https://togithub.com/charmixer/auto-changelog-action/compare/v1.3...v1.4) Update generator version to 1.16.2 ### [`v1.3`](https://togithub.com/charmixer/auto-changelog-action/releases/tag/v1.3) [Compare Source](https://togithub.com/charmixer/auto-changelog-action/compare/v1.2...v1.3) Updated to new Docker Hub Repository: https://hub.docker.com/r/githubchangeloggenerator/github-changelog-generator Using latest release: 1.16.1 ### [`v1.2`](https://togithub.com/charmixer/auto-changelog-action/compare/v1.1...v1.2) [Compare Source](https://togithub.com/charmixer/auto-changelog-action/compare/v1.1...v1.2)

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Configuration

📅 Schedule: Branch creation - At any time (no schedule defined), Automerge - At any time (no schedule defined).

🚦 Automerge: Disabled by config. Please merge this manually once you are satisfied.

♻ Rebasing: Whenever PR becomes conflicted, or you tick the rebase/retry checkbox.

🔕 Ignore: Close this PR and you won't be reminded about this update again.

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• [ ] If you want to rebase/retry this PR, click this checkbox.

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