docs: fix {:#repeat-ref} anchor in field.md (#5812)
docs: fix {:#repeat-ref} anchor in field.md (#5812)

* Remove repeat-ref for enumeration

* Add proper line breaks

Co-authored-by: Kanit Wongsuphasawat <dc2a36cfe81552efa95c0328cefeed21c9a757cc@gmail.com>

uwdata/vega-lite,vega/vega-lite,uwdata/vega-lite,vega/vega-lite,vega/vega-lite,uwdata/vega-lite,uwdata/vega-lite,vega/vega-lite,vega/vega-lite,uwdata/vega-lite