Allow text column and anchor column to be sorted by custom data field

[mollykreis]

Pull Request

🤨 Rationale

Add ability to sort a text column or anchor column by a custom data field. This implements the capability described in #2206.

This PR only includes the nimble-components changes. Angular and Blazor integration will be done in a separate PR.

👩‍💻 Implementation

• Create mixinCustomSortOrderColumnAPI that does the following for columns using it
  • Adds a sort-by-field-name attribute
  • Requires a validator with the invalidCustomSortWithGrouping flag
  • Updates the validator's invalidCustomSortWithGrouping flag based on the values of sortByFieldName, columnInternals.groupIndex, and columnInternals.groupingDisabled
• Use the mixin on the text column and anchor column
• Update storybook stories for text column and anchor column

🧪 Testing

• New unit tests for mixin
• Manually tested in storybook

✅ Checklist

• [ ] I have updated the project documentation to reflect my changes or determined no changes are needed.

[mollykreis]

@m-akinc, will you buddy this PR for me?