Bump attrs from 25.4.0 to 26.1.0

Bumps [attrs](https://github.com/sponsors/hynek) from 25.4.0 to 26.1.0.
- [Commits](https://github.com/sponsors/hynek/commits)

---
updated-dependencies:
- dependency-name: attrs
  dependency-version: 26.1.0
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

Author: dependabot[bot]

docs/requirements.txt

@@ -1,6 +1,6 @@
 alabaster==1.0.0
 atomicwrites==1.4.1
-attrs==25.4.0
+attrs==26.1.0
 Babel==2.18.0
 beautifulsoup4==4.14.3
 breathe==4.36.0

tests/constraints.txt

@@ -1,5 +1,5 @@
 numpy>=1.16.6,<2.5.0
-attrs==25.4.0
+attrs==26.1.0
 distro==1.9.0
 h5py>=3.1.0,<3.16.0
 Jinja2>=2.11.2