Update pinned services

[aktech]

Reference Issues or PRs

jhub-apps added the ability to pin services with custom thumbnail here: nebari-dev/jhub-apps#632
Adding back conda-store as pinned as nothing is pinned by default except JupyterLab and Vscode

What does this implement/fix?

Put a x in the boxes that apply

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds a feature)
• Breaking change (fix or feature that would cause existing features not to work as expected)
• Documentation Update
• Code style update (formatting, renaming)
• Refactoring (no functional changes, no API changes)
• Build related changes
• Other (please describe):

Documentation

• For new features or enhancements, a corresponding PR has been opened in the documentation repository (if applicable)
  • Link to docs PR:

Testing

• Did you test the pull request locally?
• Did you add new tests?

How to test this PR?

Any other comments?

[Adam-D-Lewis]

I believe #3163 would supercede this