Add artifacthub-repo verification and badge

[oliverguenther]

Closes #45

[changeset-bot[bot]]

🦋 Changeset detected

Latest commit: 76884dcb2be24606d362c332e2c6fa0d5d010dd7

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

| Name | Type | | ------------------------ | ----- | | @openproject/helm-charts | Patch |

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