message: Improve OSC 9;9 parsing logic & add tests
  This PR fixes the parsing of OSC 9;9 sequences with path surrounded by
  quotation marks.
  Original OSC 9;9 PR:
  Unit test added. Manually tested with oh-my-posh.
  Closes
diff: @@ -474,7 +474,19 @@ bool TerminalDispatch::DoConEmuAction(const std::wstring_view string) noexcept
  {
  if (parts.size() >= 2)
  {
  - return _terminalApi.SetWorkingDirectory(til::at(parts, 1));
  + const auto path = til::at(parts, 1);
  + // The path should be surrounded with '"' according to the documentation of ConEmu.
  + // An example: 9;"D:/"
  + if (path.at(0) == L'"' && path.at(path.size() - 1) == L'"' && path.size() >= 3)
  + {
  + return _terminalApi.SetWorkingDirectory(path.substr(1, path.size() - 2));
  + }
  + else
  + {
  + // If we fail to find the surrounding quotation marks, we'll give the path a try anyway.
  + // ConEmu also does this.
  + return _terminalApi.SetWorkingDirectory(path);
  + }
  }
  }
  