Forcing global UTM zone, causes unwanted behavior

[stevedanomodolor]

Describe the bug
A clear and concise description of what the bug is.
Due to the changes in #627, now when a user calls the service "fromll" with a lat lon outside the initially set utm, it returns (0,0) coordinates while the ros2 service still says successful.
To Reproduce
Steps to reproduce the behavior:

1. Call the service fromll with a lat lon outside the initially set datum.

Expected behavior
A clear and concise description of what you expected to happen.
It service returns successfully but returns zero coordinate.
Screenshots
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Desktop (please complete the following information):

• OS: Ubuntu
• ROS Distribution: Rolling
• robot_localization Package Version: Latest ros2 branch

Additional context
Add any other context about the problem here.
ros-navigation/navigation2#4455

[ayrton04]

FYI @Timple