Update personnel (#344)

* people: Add Rishika

* Update source/people/index.md

Co-authored-by: Insu Jang <insujang@umich.edu>

---------

Co-authored-by: Insu Jang <insujang@umich.edu>

Author: KevinRSX

source/people/index.md

@@ -33,6 +33,7 @@ excerpt: "SymbioticLab current & past members"
 1. Wonbin Jin (CSE MSE)
 1. Jisang Ahn (CS-LSA BS)
 1. Letian Ruan (CSE BSE)
+1. Rishika Kalidindi (CSE MSE)
 
 ## Past Members
 1. Jack Kosaian (CSE BSE) → Ph.D. @CMU