Make IMF host devicetest apk debuggable to support compat change test

 * The test in question was added by
 Ibf7bfacf6f4732a849dafe96b8ff16496b0daba5
 * On "user" build overriding app-compat flag requires the target to
 be built with android:debuggable="true".
 * The test in question has been failing on "user" builds since its
 beginning because of the above restriction.
 * This CL takes care of the above restriction.
 * Test itself remains to be the same hence basically there is no risk.

Fix: 181569616
Test: repro on a user build device and verify the test passes after fix
 1. lunch blueline-user
 2. make -j
 3. Flash the image
 4. make -j CtsInputMethod1 \
                  CtsInputMethod2 \
                  CtsInputMethodServiceDeviceTests \
                  CtsInputMethodServiceEventProvider \
                  CtsInputMethodServiceHostTestCases \
                  EditTextApp
 5. atest CtsInputMethodServiceHostTestCases:InlineSuggestionsRequestHostTest

Change-Id: If4f31e05e95d54a038f643ea0b5d4725d37f384e
1 file changed