Update Anonymous Column documents to reference ability to use strings

[lrljoe]

Docs Only update - add to the Anonymous Column docs

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[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Comparison is base (69a64c3) 89.08% compared to head (2ca71ee) 89.08%.

Additional details and impacted files

```diff @@ Coverage Diff @@ ## develop #1588 +/- ## ========================================== Coverage 89.08% 89.08% Complexity 1307 1307 ========================================== Files 99 99 Lines 3078 3078 ========================================== Hits 2742 2742 Misses 336 336 ```

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