Include 3D and 4D read options for all met variables (#528)

# CABLE

Thank you for submitting a pull request to the CABLE Project.

## Description

Fixes #525 

I decided to add the possibility of 3D or 4D formats in met forcings for
all variables, except LAI, even if the issue was seen only for CO2air.
This makes all the variables treatment identical. LAI was excluded
because it is a different case with more complex conditions. This
focused only on the "mask" option of `metGrid` as it is the most widely
used and I don't have a test case for the "land" option.

## Type of change

Please delete options that are not relevant.

- [X] Bug fix

## Checklist

- [X] The new content is accessible and located in the appropriate
section
- [X] I have checked that links are valid and point to the intended
content
- [X] I have checked my code/text and corrected any misspellings

## Testing

- [ ] Are the changes bitwise-compatible with the main branch? If
working on an optional feature, are the results bitwise-compatible when
this feature is off? If yes, copy benchcab output showing successful
completion of the bitwise compatibility tests or equivalent results
below this line.

- [X] Are the changes non bitwise-compatible with the main branch
because of a bug fix or a feature being newly implemented or improved?
If yes, add the link to the modelevaluation.org analysis versus the main
branch or equivalent results below this line.

As expected all bitwise-comparison tests have failed:

```
2025-01-15 12:10:39,793 - INFO - benchcab.benchcab.py:391 - 168 failed, 0 passed
```

[Results from
modelevaluation.org](https://modelevaluation.org/analyses/anywhere/nFcjg4qqHGPkB9sqE/s6k22L3WajmiS9uGv/AGbw9TkEdqikdySne/all)
show little to no differences which is not surprising considering the
changes impact the CO2 input in particular.
Please add a reviewer when ready for review.


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