The current method of reading the input file in JopOptionSvc leads to undefined behavior errors in the ATLAS debug build on el9/gcc13/LCG_104 (see ATEAM-937). Use std::stringstream instead, which is also supposedly faster.
Also rewrite GetLastLineAndColumn to not read the file twice.
/cvmfs/sft.cern.ch/lcg/releases/gcc/13.1.0-b3d18/x86_64-el9/include/c++/13.1.0/bits/basic_string.h:278:29: runtime error: execution reached an unreachable program point
#0 0x423f2b in std::__cxx11::basic_string, std::allocator >::_M_is_local() const /cvmfs/sft.cern.ch/lcg/releases/gcc/13.1.0-b3d18/x86_64-el9/include/c++/13.1.0/bits/basic_string.h:278
#1 0x423dd2 in std::__cxx11::basic_string, std::allocator >::_M_dispose() /cvmfs/sft.cern.ch/lcg/releases/gcc/13.1.0-b3d18/x86_64-el9/include/c++/13.1.0/bits/basic_string.h:293
#2 0x7f3035ae0506 in void std::__cxx11::basic_string, std::allocator >::_M_construct > >(std::istreambuf_iterator >,
std::istreambuf_iterator >, std::input_iterator_tag) /cvmfs/sft.cern.ch/lcg/releases/gcc/13.1.0-b3d18/x86_64-el9/include/c++/13.1.0/bits/basic_string.tcc:200
#3 0x7f3035ad93f9 in std::__cxx11::basic_string, std::allocator >::basic_string >, void>(std::istreambuf_iterator >,
std::istreambuf_iterator >, std::allocator const&) /cvmfs/sft.cern.ch/lcg/releases/gcc/13.1.0-b3d18/x86_64-el9/include/c++/13.1.0/bits/basic_string.h:764
#4 0x7f3035ad5e99 in ParseStream > > >, Gaudi::Parsers::Skipper
Grammar > > > > > > /build/atnight/localbuilds/nightlies/Athena/main/build/build/AthenaExternal
s/src/Gaudi/GaudiCoreSvc/src/JobOptionsSvc/Parser.cpp:52
#5 0x7f3035ad5350 in ParseFile > > >, Gaudi::Parsers::SkipperGr
ammar > > > > > > /build/atnight/localbuilds/nightlies/Athena/main/build/build/AthenaExternals/
src/Gaudi/GaudiCoreSvc/src/JobOptionsSvc/Parser.cpp:104
#6 0x7f3035ad4e10 in Gaudi::Parsers::Parse(Gaudi::Parsers::Position const&, std::basic_string_view >, std::basic_string_view >, Gaudi::Parsers::IncludedFiles*, Gaudi::Parsers::M
essages*, Gaudi::Parsers::Node*) /build/atnight/localbuilds/nightlies/Athena/main/build/build/AthenaExternals/src/Gaudi/GaudiCoreSvc/src/JobOptionsSvc/Parser.cpp:123
#7 0x7f3035ad4d7b in Gaudi::Parsers::Parse(std::basic_string_view >, std::basic_string_view >, Gaudi::Parsers::IncludedFiles*, Gaudi::Parsers::Messages*, Gaudi::Parsers::Node*)
/build/atnight/localbuilds/nightlies/Athena/main/build/build/AthenaExternals/src/Gaudi/GaudiCoreSvc/src/JobOptionsSvc/Parser.cpp:117
#8 0x7f3035a48bc3 in Gaudi::Parsers::ReadOptions(std::basic_string_view >, std::basic_string_view >, Gaudi::Parsers::Messages*, Gaudi::Parsers::Catalog*, Gaudi::Parsers::Units*,
Gaudi::Parsers::PragmaOptions*, Gaudi::Parsers::Node*) /build/atnight/localbuilds/nightlies/Athena/main/build/build/AthenaExternals/src/Gaudi/GaudiCoreSvc/src/JobOptionsSvc/Analyzer.cpp:391
#9 0x7f3035a5b4a7 in JobOptionsSvc::readOptions(std::basic_string_view >, std::basic_string_view >) /build/atnight/localbuilds/nightlies/Athena/main/build/build/AthenaExternals/
src/Gaudi/GaudiCoreSvc/src/JobOptionsSvc/JobOptionsSvc.cpp:256