Fix if clauses

During a refactor, we introduced updated the method used to
verify signatures. The "&& additionalTest" clauses were added
to the wrong if statement [off-by-one]. So, we were performing
a compat signature check when we shouldn't and not throwing
an exception when we should.

Change-Id: Ie479be5b254b9b13451ab07a07d20a68c7b828ad
Fixes: 69053002
Test: cts-tradefed run commandAndExit cts-dev -m CtsAppSecurityHostTestCases -t android.appsecurity.cts.AppSecurityTests#testSharedUidDifferentCerts