x11/hyprlock: unbreak build with libc++ 19

src/renderer/widgets/IWidget.cpp:104:44: error: no member named 'current_zone' in namespace 'std::chrono'

104 |     const auto current_zone = std::chrono::current_zone();
    |                               ~~~~~~~~~~~~~^

src/renderer/widgets/IWidget.cpp:113:44: error: no member named 'current_zone' in namespace 'std::chrono'

113 |     const auto current_zone = std::chrono::current_zone();
    |                               ~~~~~~~~~~~~~^

Reported by: pkg-fallout