Bump xarray from 2025.1.2 to 2025.6.1

Bumps [xarray](https://github.com/pydata/xarray) from 2025.1.2 to 2025.6.1.
- [Release notes](https://github.com/pydata/xarray/releases)
- [Changelog](https://github.com/pydata/xarray/blob/main/HOW_TO_RELEASE.md)
- [Commits](pydata/xarray@v2025.01.2...v2025.06.1)

---
updated-dependencies:
- dependency-name: xarray
  dependency-version: 2025.6.1
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

requirements_pinned.txt

@@ -9,6 +9,6 @@ pydantic==2.12.5
 pyglotaran==0.7.3
 ruamel-yaml==0.18.17
 tabulate==0.9.0
-xarray==2025.1.2
+xarray==2025.6.1
 # Fixes for pydata-sphinx-theme until a new upstream release is available
 git+https://github.com/s-weigand/pydata-sphinx-theme.git@fixes