tz_manager: Fix character offset not advancing

src/core/hle/service/time/time_zone_manager.cpp

@@ -149,6 +149,7 @@ static constexpr bool GetInteger(const char* name, int& offset, int& value, int
         if (value > max) {
             return {};
         }
+        offset++;
         temp = name[offset];
     } while (IsDigit(temp));