Fixed dangling file openings

[ledm]

Pull request checklist

close #581.

Minor change to the loading method to "with as" instead of file = load_file(). This makes it more error proof and safely closes netcdf files correctly, even if we get an exception or seg fault along the way.

Please check if your PR fulfills the following requirements:

• [ ] Tests for the changes have been added (for bug fixes / features)
• [ ] Docs have been reviewed and added / updated if needed (for bug fixes / features)
  • Some docs updates need to be made in the COAsT-site repo, in a separate PR. See contributing to documentation for details.
• [ ] Build (./build.sh) was run locally and no errors reported
• [ ] Lint (pylint .) has passed locally and any fixes were made for failures

Pull request type

Please check the type of change your PR introduces: - [x] Bugfix - [ ] Feature - [x] Code style update (formatting, renaming) - [ ] Refactoring (no functional changes, no api changes) - [ ] Build related changes - [ ] Documentation content changes - [ ] Other (please describe): Updated loading method to "with as" instead of `file = load_file()`. This makes it more error proof and safely closes netcdf files correctly, even if we get an exception or seg fault along the way. ## What is the current behavior?

Issue URL: #581

What is the new behavior?

-

Checklist

• [ ] Code compiles correctly
• [ ] Created tests which fail without the change (if possible)
• [ ] All tests passing
• [ ] Extended the README / documentation, if necessary
• [ ] Added myself / the copyright holder to the AUTHORS file

Does this introduce a breaking change?

• [ ] Yes
• [ ] No

Other information

[ledm]

Note that I've only changed the coast.py so far. This should probably be changed in:

• [ ] altimetry.py: self.dataset = xr.open_dataset(file, chunks=chunks)
• [ ] altimetry.py: self.dataset = xr.open_mfdataset(
• [x] coast.py: with xr.open_dataset(file, chunks=chunks) as xrfile:
• [x] coast.py: with xr.open_mfdataset(directory_to_files,
• [ ] glider.py: self.dataset = xr.open_dataset(file_path, chunks=chunks)
• [ ] gridded.py: dataset_domain = xr.open_dataset(fn_domain)
• [ ] gridded.py: ds_dom = xr.open_dataset(dom_fn).squeeze().rename({"z": "z_dim", "x": "x_dim", "y": "y_dim"})
• [ ] oceanparcels.py: self.dataset = xr.open_dataset(file_path, chunks=self.chunks)
• [ ] profile.py: self.dataset = xr.open_dataset(fn_en4, chunks=chunks)
• [ ] profile.py: data_tmp = xr.open_dataset(file, chunks=chunks)
• [ ] profile.py: self.dataset = xr.open_dataset(fn_wod, chunks=chunks)

[jpolton]

Failed test is due to GitAction not being able to commit to Forked branch. It regenerates unit_testing/unit_test_contents.txt. But no changes are needed. And associate ticket is created #591 .