Update deps to add yamale

[Zeitsperre]

Pull Request Checklist:

• This PR addresses an already opened issue (for bug fixes / features)
  • This PR fixes Yamale error validating data with schema for xscen conversion #1595
• Tests for the changes have been added (for bug fixes / features)
  • (If applicable) Documentation has been added / updated (for bug fixes / features)
• CHANGES.rst has been updated (with summary of main changes)
  • Link to issue (:issue:number) and pull request (:pull:number) has been added

What kind of change does this PR introduce?

• Adds yamale to the core dependencies

Does this PR introduce a breaking change?

Yes, dependencies have changed.

Other information:

yamale code can be found in the core of the library. It might be a good idea to perform an analysis of all existing deps to ensure that the necessary entries are all listed.

[github-actions]

Note
It appears that this Pull Request modifies the main.yml workflow.

On inspection, the XCLIM_TESTDATA_BRANCH environment variable is set to the most recent tag (v2023.12.14).

No further action is required.

[coveralls]

coverage: 90.273%. remained the same
when pulling 444eee3 on update-deps
into 07150a7 on master.