Fixes #2007 : Update objenesis dep to 3.2

[PaulKlauser]

Allows for building android instrumentation tests with minsdk < 26

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[TimvdLippe]

We will also need to update android.gradle to use the latest version of objenesis again. E.g. we would need to effectively revert #2024 so that both android.gradle and the main project use the same version of objenesis.

[TimvdLippe]

This LGTM! Just to confirm: have you locally applied these changes and ran your Android tests on SDK <26 and confirmed they are indeed running as expected? I would like to avoid publishing a breaking release once again.

[PaulKlauser]

Good call, just published the artifacts locally and gave it a go. Everything looks good, building and running tests on API 24!

[TimvdLippe]

Great, thanks for the confirmation!