Fix MigrateRepositoryService spec when repo is already on disk

Running this after
spec/services/projects/hashed_storage/migrate_repository_service_spec.rb would fail
previously, because the new repository path already existed on disk. As this spec expects
the new repository path to not exist on disk prior to being moved, we should clear out
the test repos before running.

spec/ee/spec/services/ee/projects/hashed_storage/migrate_repository_service_spec.rb

@@ -10,6 +10,10 @@ describe Projects::HashedStorage::MigrateRepositoryService do
     set(:primary) { create(:geo_node, :primary) }
     set(:secondary) { create(:geo_node) }
 
+    before do
+      TestEnv.clean_test_path
+    end
+
     it 'creates a Geo::HashedStorageMigratedEvent on success' do
       expect { service.execute }.to change(Geo::EventLog, :count).by(1)