Rename BuildOutcomes

```
Ambiguous occurrence ‘BuildOutcomes’
It could refer to
either ‘Distribution.Client.ProjectBuilding.BuildOutcomes’,
imported from ‘Distribution.Client.ProjectBuilding’ at tests/IntegrationTests2.hs:23:1-42
(and originally defined in ‘Distribution.Client.ProjectBuilding.Types’)
or ‘Distribution.Client.InstallPlan.BuildOutcomes’,
imported from ‘Distribution.Client.InstallPlan’ at tests/IntegrationTests2.hs:73:1-38
```

This is terrible.

If there are other types (as there are) which share the same name, those have to be renamed too. This kind of surprises kill any flow you might have.

Start with the ambiguous imports in tests/IntegrationTests2.hs, then inspect the BuildOutcomes definitions in Distribution.Client.ProjectBuilding.Types and Distribution.Client.InstallPlan. Identify the other same-named types and their references. Done means the conflicting names are distinct and the affected tests compile without an ambiguous occurrence.

Written by the indexing model from the issue text.