Add benwright@webrtc.org to test/fuzzers/OWNERS.

I am planning to do a lot of work on adding additional fuzzing to WebRTC in Q1
of 2019. Given the limited number of available owners in this directory, and it
being non-prod I think this makes sense.

Bug: webrtc:10117
Change-Id: If2ad52fbce120c4d2bce51f4bfed99d83d78e6a5
Reviewed-on: https://webrtc-review.googlesource.com/c/117043
Reviewed-by: Alex Loiko <aleloi@webrtc.org>
Reviewed-by: Sam Zackrisson <saza@webrtc.org>
Reviewed-by: Henrik Lundin <henrik.lundin@webrtc.org>
Commit-Queue: Benjamin Wright <benwright@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#26250}
diff --git a/test/fuzzers/OWNERS b/test/fuzzers/OWNERS
index 1ba807e..020cfce 100644
--- a/test/fuzzers/OWNERS
+++ b/test/fuzzers/OWNERS
@@ -1,3 +1,4 @@
 henrik.lundin@webrtc.org
 aleloi@webrtc.org
 saza@webrtc.org
+benwright@webrtc.org