Add updated xr_interpolate func and tests

[robbibt]

Proposed changes

This PR updates the existing interpolate_2d function into a brand new xr_interpolation function. Compared to interpolate_2d, this function:

• Supports a geopandas.GeoDataFrame points dataset as an input
• Automatically interpolates all numeric columns in this dataset
• Also supports Inverse Distance Weighted interpolation, with option to restrict the interpolation to k nearest neighbours.

Example Inverse Distance Weighted interpolated xarray output for a point gdf containing 7 columns:

Have added comprehensive tests, and deprecated interpolate_2d to be removed at a later date.

Checklist

(Replace [ ] with [x] to check off)

• [ ] Notebook created using the DEA-notebooks template
• [x] Remove any unused Python packages from Load packages
• [ ] Remove any unused/empty code cells
• [ ] Remove any guidance cells (e.g. General advice)
• [x] Ensure that all code cells follow the PEP8 standard for code. The jupyterlab_code_formatter tool can be used to format code cells to a consistent style: select each code cell, then click Edit and then one of the Apply X Formatter options (YAPF or Black are recommended).
• [ ] Include relevant tags in the final notebook cell (refer to the DEA Tags Index, and re-use tags if possible)
• [ ] Clear all outputs, run notebook from start to finish, and save the notebook in the state where all cells have been sequentially evaluated
• [ ] Test notebook on both the NCI and DEA Sandbox (flag if not working as part of PR and ask for help to solve if needed)
• [ ] If applicable, update the Notebook currently compatible with the NCI|DEA Sandbox environment only line below the notebook title to reflect the environments the notebook is compatible with
• [x] Check for any spelling mistakes using the DEA Sandbox's built-in spellchecker (double click on markdown cells then right-click on pink highlighted words). For example: