[New Extension]: pg_repack

### Is there an existing issue for this extension request?

- [x] I have searched for an existing issue, and could not find a duplicate request.

### Extension Name

pg_repack

### Project Repository URL

https://github.com/reorg/pg_repack

### Extension Website URL (Optional)

https://reorg.github.io/pg_repack/

### Short Description

`pg_repack` is a PostgreSQL extension which lets you remove bloat from tables and indexes, and optionally restore the physical order of clustered indexes.

`pg_repack` extension works online.

### Main LICENSE Link

https://github.com/reorg/pg_repack?tab=BSD-3-Clause-1-ov-file#readme

### License Compliance

- [x] The extension's license (linked above) complies with the list of allowed licenses.

### Known Dependent Extensions

None

### Component Owner and Maintenance Commitment

- [x] I/My organization commit to becoming the Component Owner and maintaining the extension image in the future.

### Additional Notes (Optional)

No license file exists in the repoistory, but this project is using `BSD-3-Clause` license

### GitHub Handles of Component Owners

@thomasboussekey

### Code of Conduct

- [x] I agree to follow this project's Code of Conduct

Die Anfrage nennt pg_repack und verlinkt dessen Upstream-Repository und Website, nennt jedoch keine Dateien, Tests oder Build-Einstiegspunkte. Untersuche zunächst, wie bestehende PostgreSQL-Erweiterungen in diesem Repository paketiert werden, und überprüfe anschließend, dass pg_repack im resultierenden Container-Image verfügbar ist und dass die BSD-3-Clause-Lizenzierung sowie die Angaben zum Eigentümer dokumentiert sind.

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