Swap default for disableTestApiChecks.

There are more runners than those updated in tradefed/testtype/, which donot/cannot push --no-test-api-checks arg to `am instrument`. Instead reverse the default, so that by default `am instrument` disables test api enforcement policy.

Test: atest CtsHiddenApiBlacklistApi27TestCases \
        CtsHiddenApiBlacklistApi28TestCases \
        CtsHiddenApiBlacklistCurrentApiTestCases \
        CtsHiddenApiBlacklistDebugClassTestCases \
        CtsHiddenApiBlacklistTestApiTestCases \
        CtsAppSecurityHostTestCases:android.appsecurity.cts.ExternalStorageHostTest#testMediaEscalation \
        CtsAppSecurityHostTestCases:android.appsecurity.cts.StorageHostTest#testVerify \
        CtsAppSecurityHostTestCases:android.appsecurity.cts.DirectBootHostTest#testDirectBootNative
Exempt-From-Owner-Approval: small fix
Bug: 133832325
Change-Id: Id1870cdd4bb0a51bddede24afd7f87d6e5ec766c