Merge pull request #1215 from buildpacks/fix-spelling-1211

Polish #1211 - Add Concurrency support
Signed-off-by: David Freilich <freilich.david@gmail.com>

Author: dfreilich

internal/registry/registry_cache.go

@@ -187,7 +187,15 @@ func (r *Cache) CreateCache() error {
 		return err
 	}
 
-	return os.Rename(w.Filesystem.Root(), r.Root)
+	err = os.Rename(w.Filesystem.Root(), r.Root)
+	if err != nil {
+		if err == os.ErrExist {
+			// If pack is run concurrently, this action might have already occurred
+			return nil
+		}
+		return err
+	}
+	return nil
 }
 
 func (r *Cache) validateCache() error {