Change website links in metadata.yaml (16)

[a-velasco]

This PR updates the product page URL and adds a Matrix link in the metadata.yaml.

These changes will reflect in the Charmhub UI at charmhub.io/postgresql?channel=16/<channel> whenever the channel gets its next update.

Checklist

• I have added or updated any relevant documentation.
• I have cleaned any remaining cloud resources from my accounts.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 69.82%. Comparing base (28b6219) to head (dadd408).
⚠️ Report is 2 commits behind head on 16/edge.

❌ Your project status has failed because the head coverage (69.82%) is below the target coverage (70.00%). You can increase the head coverage or adjust the target coverage.

Additional details and impacted files

@@           Coverage Diff            @@
##           16/edge    #1281   +/-   ##
========================================
  Coverage    69.82%   69.82%           
========================================
  Files           16       16           
  Lines         4149     4149           
  Branches       658      658           
========================================
  Hits          2897     2897           
  Misses        1045     1045           
  Partials       207      207           

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[Copilot]

Pull Request Overview

This PR updates the metadata.yaml file to reflect organizational changes and improve contact information for the PostgreSQL charm.

• Updated the primary website URL from ubuntu.com to canonical.com
• Removed the CharmHub URL from the website list while retaining the GitHub repository link
• Added a contact field with a Matrix channel link for direct communication

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[taurus-forever]

@copilot rebase on top of 16/edge

[Copilot]

@taurus-forever I've opened a new pull request, #1327, to work on those changes. Once the pull request is ready, I'll request review from you.