Bump blinker from 1.7.0 to 1.8.1

Bumps [blinker](https://github.com/pallets-eco/blinker) from 1.7.0 to 1.8.1.
- [Release notes](https://github.com/pallets-eco/blinker/releases)
- [Changelog](https://github.com/pallets-eco/blinker/blob/main/CHANGES.rst)
- [Commits](pallets-eco/blinker@1.7.0...1.8.1)

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

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

requirements.txt

@@ -26,7 +26,7 @@ gunicorn[eventlet]==21.2.0
 jsonschema==4.20.0
 apispec==6.3.1
 apispec-webframeworks==0.5.2
-blinker==1.7.0
+blinker==1.8.1
 Babel==2.12.1
 PyYAML==6.0.1
 python-frontmatter==1.0.1