Update "community" to "contributor" for Vivek

Signed-off-by: Alex Ellis (OpenFaaS Ltd) <alexellis2@gmail.com>

Author: alexellis

_staff_members/vivek.md

@@ -5,5 +5,5 @@ image_path: /images/author/vivek.png
 github_username: viveksyngh
 twitter_username: viveksyngh
 linkedin_username: viveksyngh
-blurb: Community <a href="https://twitter.com/openfaas">@openfaas</a>.
+blurb: Contributor <a href="https://twitter.com/openfaas">@openfaas</a>.
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