Writing tests caught a bug in PR #3393, which enabled
installing more than one package per `pkg` execution.
In converting the module's install/upgrade code to a
queue structure, check_mode got broken because the count
of actions performed was only updated in the `if not check_mode`
block that invokes `pkg`. This two-line change counts
the number of actions in the queue when check mode is
enabled.
`upgrade_packages()` only looked for the string
"Number of packages to be upgraded", but the
`pkg upgrade` command also reports "Number of packages to be
reinstalled". Reinstallation occurs when package metadata other
than version changes (e.g. build options, single architecture to `*`
architecture). In any other respect, though, a required
reinstallation is the same as an upgrade.
