Pass `ModelArray` to `Xios.write`, rather than array of `double`s

[jwallwork23]

Pass ModelArray to Xios.write, rather than array of doubles

Fixes #544

Task List

• [x] Defined the tests that specify a complete and functioning change (It may help to create a design specification & test specification)
• [ ] Implemented the source code change that satisfies the tests
• [ ] Documented the feature by providing worked example
• [ ] Updated the README or other documentation
• [ ] Completed the pre-Request checklist below

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Change Description

In the existing implementation of the Xios class, its write method accepts a C-style array of doubles, along with its dimensions in each direction. The approach adopted here - better in line with neXtSIM-DG's approach - is to instead pass a ModelArray, which knows about both the data and dimensions.

NOTE: #559 will need to be merged first.

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Test Description

Updated the tests accordingly.

• [x] Implement changes in XIOS integration test.
• [ ] Fix linking/build for XIOS integration test.

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Pre-Request Checklist

• [x] The requirements of this pull request are fully captured in an issue or design specification and are linked and summarised in the description of this PR
• [ ] No new warnings are generated
• [ ] The documentation has been updated (or an issue has been created to track the corresponding change)
• [ ] Methods and Tests are commented such that they can be understood without having to obtain additional context
• [ ] This PR/Issue is labelled as a bug/feature/enhancement/breaking change
• [ ] File dates have been updated to reflect modification date
• [ ] This change conforms to the conventions described in the README