Add <settingspanel> link component for opening setting panel from template code

[na9da]

Split from #7626
Required for UX in #6845

What this PR does

Adds a <settingspanel> custom component to use from template code (like short-report/ feature info etc) that when clicked pops open the Settings panel menu.

Example definition:

{
  "catalog": [
    {
      "type": "geojson",
      "name": "Bike racks",
      "url": "test/bike_racks.geojson",
      "hideLegendInWorkbench": true,
      "shortReport": "<settingspanel title='Open map settings' />Click to open Map settings</settingspanel> and choose a different base map."
    }
  ]
}

Test me

• Open this CI link that uses this catalog definition
• Click the setting panel link in the short report for the workbench item
• Observe it opens the Setting panel menu

Checklist

• There are unit tests to verify my changes are correct or unit tests aren't applicable (if so, write quick reason why unit tests don't exist)
• I've updated relevant documentation in doc/.
• I've updated CHANGES.md with what I changed.
• I've provided instructions in the PR description on how to test this PR.