Remove mateuszc@google.com from tests/OWNERS

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memberships and affiliations.
If this change is unnecessary or in error, vote CR -1 and the bot
will abandon it. Vote CR +1/2 to approve this change.

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https://android-review.googlesource.com/q/mateuszc@google.com

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Change-Id: I0c1c61d68c098cb91f1c9721e8b1902903a0e1a2

tests/OWNERS

@@ -3,4 +3,3 @@ vadimt@google.com
 sunnygoyal@google.com
 winsonc@google.com
 hyunyoungs@google.com
-mateuszc@google.com