CmdPal: Hide selection indicator (pill) from items in the context menu

[jiripolasek]

Summary of the Pull Request

This PR removes the selection indicator from the list view used for the context menu to maintain consistency with Fluent UI design guidelines.

Pictures? Pictures!

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PR Checklist

• [ ] Closes: #xxx

• [ ] Communication: I've discussed this with core contributors already. If the work hasn't been agreed, this work might be rejected
• [ ] Tests: Added/updated and all pass
• [ ] Localization: All end-user-facing strings can be localized
• [ ] Dev docs: Added/updated
• [ ] New binaries: Added on the required places
  • [ ] JSON for signing for new binaries
  • [ ] WXS for installer for new binaries and localization folder
  • [ ] YML for CI pipeline for new test projects
  • [ ] YML for signed pipeline
• [ ] Documentation updated: If checked, please file a pull request on our docs repo and link it here: #xxx

Detailed Description of the Pull Request / Additional comments

Validation Steps Performed