fixup! Test suite for FunctionCallGraph

Author: cameel

test/libsolidity/analysis/FunctionCallGraph.cpp

@@ -145,9 +145,8 @@ void checkCallGraphExpectations(
 	);
 	for (string const& contractName: _expectedEdges | views::keys)
 	{
-		set<string> emptySet;
 		soltestAssert(
-			(ranges::views::set_difference(valueOrDefault(_expectedCreatedContractSets, contractName, emptySet), _expectedEdges | views::keys)).empty(),
+			(ranges::views::set_difference(valueOrDefault(_expectedCreatedContractSets, contractName, {}), _expectedEdges | views::keys)).empty(),
 			"Inconsistent expectations: contract expected to be created but not to be present in the source file."
 		);
 	}