fix for missing images (#52)

Author: SachinVenugopalan30

public/headshots/placeholder.png

@@ -32,7 +32,7 @@
       "name": "Tejas Balemarthy",
       "role": "Treasurer",
       "email": "pbalemar@asu.edu",
-      "image": "/headshots/tejas.jpg"
+      "image": "/headshots/placeholder.png"
     },
     {
       "name": "Ruby Gonzalez Alvarado",
@@ -140,7 +140,7 @@
       "name": "Nathan Narrik",
       "role": "Events Developer",
       "email": "nnarrik@asu.edu",
-      "image": "/headshots/nathan.jpg"
+      "image": "/headshots/placeholder.png"
     }
   ],
   "Community": [
@@ -172,7 +172,7 @@
       "name": "Ryan Groholski",
       "role": "Community Officer",
       "email": "rgrohols@asu.edu",
-      "image": "/headshots/ryanGroholski.jpg"
+      "image": "/headshots/placeholder.png"
     }
   ],
   "Marketing": [