Improve Installed status condition setting

[everettraven]

In a recent sync call on slack, we identified that our current InstalledBundleGetter doesn't return sufficient information to give us a clear picture to determine the appropriate Installed condition state.

After #1296 is fixed, we can implement the following behavior for the Installed condition to adhere to the level-based approach that is expected of Kubernetes controllers:

• If we get a nil value and no error from the InstalledBundleGetter - nothing installed (i.e Installed == False)
• If we get an error from the InstalledBundleGetter - Installed condition is set to Unknown
• If we get a non-nil value from the InstalledBundleGetter and an error happens in a step leading to successful upgrade, Installed condition set to True and Progressing condition contains the upgrade failure