Build shim_not_pre_installed shim artifact with proper sdk target

Without an explicit AndroidManifest, the autogenrated AndroidManifest
targets the latest sdk, which can be a development build instead of
release build. For the purpose of this particular artifact, directly
targeting 29 is fine.

This is also consistent with other APEX artifacts which also have their
own explicit AndroidManifest property.

Bug: 188910443
Test: atest StagedInstallTest#testInstallStagedNonPreInstalledApex_Fails
Change-Id: Idd434e097ba5128a0de30819f6627987dce0df85
2 files changed