(maint) Cleanup specs for the `module` Face’s `install` action.

Prior to this change, the specs relied on a fragile chain of stubbed
expectations, which changes elsewhere in the application have rendered
incorrect and non-operational.

This change aims to improve these specs by stubbing less and making
more robust assertions about the data.
Merge pull request #2898 from pvande/maint/stable/cleanup-module-install-spec

(maint) Cleanup specs for the `module` Face’s `install` action.
(PUP-2943) Add PMT --ignore-changes

Prior to this commit there was no way to only ignore local changes to a module.
You had to --force when upgrading/uninstalling, which could potentially have other
repurcussions.
This commit adds the --ignore-changes flag, so a user can specify that they don't
care about local file changes but do not want to force anything else.
(PUP-2943) Uninstall/upgrade ignore changes spec

Adding more spec tests for the --ignore-changes flag on uninstall/upgrade
(PUP-2943) Clean ignore-changes uninstall logic