[e2e] Android: Remove warning, bump AGP

[ened]

Description

Currently, android build creates the warning message:

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[ened]

@xster you need to share how you made 26a9a22 pass the CI. :)
The commit removes the MainActivity class, which the MainActivityWithPermissionsTest test depends on. It only failed now - but not at the time of your commit.

[digiter]

RSLGTM