Launching updated package after finishing package installer

The updated package was not started after package update completed.
That's because the package installer were started on the app task,
start the app again would bring the same task.

Therefore, let's finish all the package installer activities before
launching the updated app.

Meanwhile, FLAG_ACTIVITY_CLEAR_TOP is used to clear the Setting's
activity instead of reorder the PackageInstallerActivity to front,
which could remove the Settings activity during the update flow.

Bug: 282618106
Test: verified locally with package update
Change-Id: Ie5942d1a9745ea9e3e9f0c04fa5d0ad332f23c93