[Android] Remove aura tester entry in chromium.android.json.
[Android] Remove aura tester entry in chromium.android.json.

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BUG=
TBR=martiniss@chromium.org,stip@chromium.org

Review URL: https://codereview.chromium.org/1691563002

Cr-Commit-Position: 972c6d2dc6dd5efdad1377c0d224e03eb8f276f7@{#374781}

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