Currently, if a package has a dependency from another repository and patches it,
generation of the patch cache will fail. Concretization succeeds if a fixed patch
cache is in place.
- [x] don't assume that patched dependencies are in the same repo when indexing
- [x] add some test fixtures to support multi-repo tests.
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Signed-off-by: Todd Gamblin <tgamblin@llnl.gov>
Co-authored-by: Todd Gamblin <tgamblin@llnl.gov>