chore(starters): add RG-Portfolio starter (#21698)
chore(starters): add RG-Portfolio starter (#21698)

* chore(starters): add RG-Portfolio starter

* chore: format

* chore(starters): RG-Portfolio starter Remove invalid categories

Co-authored-by: LB <8468275f0d120527324004754c3d088324306866@gatsbyjs.com>
Co-authored-by: GatsbyJS Bot <313a651c59fdaade90d152972001707d94b0975c@gmail.com>

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