fix: make SerializeSTL.h ostream overloads available

Phys/SelAlgorithms/src/TestFunctors.h

@@ -190,6 +190,7 @@ namespace ThOr::Functors::Tests::detail {
 } // namespace ThOr::Functors::Tests::detail
 
 namespace ThOr::Functors::Tests {
+  using GaudiUtils::operator<<;
   /** @class  ThOr::Functors::Tests::InitialiseAndOptionallyEvaluate TestFunctors.h
    *  @tparam SkipEvaluation       Should this algorithm just instantiate the
    *                               functors and perform initialize-time checks, or
@@ -271,8 +272,7 @@ namespace ThOr::Functors::Tests {
       this->debug() << "dump_tag_names: " << dump_tag_names << endmsg;
       this->debug() << "filter_tag_names: " << filter_tag_names << endmsg;
       // Shorthand for below
-      using GaudiUtils::operator<<;
-      auto const        exception = [&]( std::string name ) {
+      auto const exception = [&]( std::string name ) {
         std::ostringstream oss;
         oss << std::move( name ) << " [dump_tag_names = " << dump_tag_names
             << ", filter_tag_names = " << filter_tag_names << ']';
@@ -448,8 +448,7 @@ namespace ThOr::Functors::Tests {
                       boost::mp11::mp_list<filter_tags...>,
                       std::integer_sequence<SIMDWrapper::InstructionSet, Backends...> ) const {
       // Shorthand for below
-      using GaudiUtils::operator<<;
-      auto              exception = [&]( std::string_view name ) {
+      auto exception = [&]( std::string_view name ) {
         std::ostringstream oss;
         oss << name << " [dump_tag_names = " << std::array{dump_tags::name()...} << ']';
         return GaudiException{oss.str(), prettyName() + "::operator()", StatusCode::FAILURE};