The package resourceCount incorrectly includes PCIs with a removedTimestamp

The package resourceCount property includes all PCIs in the package, but PCIs which have a removedTimestamp should be excluded from the count because these are titles that have been removed/deleted from the package.

This results in the resourceCount being different from the number of titles shown as belonging to the package in the UI in the case that some PCIs have a removedTimestamp.

The resourceCount is calculated by getResourceCount in Pkg.groovy