Remove hansson@google.com from OWNERS

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memberships and affiliations.
If this change is unnecessary or in error, vote the lowest CR value
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See the owner's recent activity for context:
https://android-review.googlesource.com/q/hansson@google.com

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Change-Id: Ibc0310f63b34c35dff0d5cdc5f3ea71c72b4f99c