Disable OnBackInvoked for InputCtsActivity

Disable the `OnBackInvokedCallback` for the `InputCtsActivity` so that
configurations that have a callback registered don't consume the
`KEYCODE_BACK` events that these tests generate.

Fixes: 314896983
Test: atest CtsHardwareTestCases
(cherry picked from https://googleplex-android-review.googlesource.com/q/commit:aa7e19ad350a3ba44ad3a834dbc215ec48e0567e)
Merged-In: I96358a11266581d33d39938886ca0a95915c2609
Change-Id: I96358a11266581d33d39938886ca0a95915c2609
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1 file changed