build(deps): bump poetry-plugin-export from 1.8.0 to 1.9.0 in /devtools (#3033)

Bumps [poetry-plugin-export](https://github.com/python-poetry/poetry-plugin-export) from 1.8.0 to 1.9.0.
- [Release notes](https://github.com/python-poetry/poetry-plugin-export/releases)
- [Changelog](https://github.com/python-poetry/poetry-plugin-export/blob/main/CHANGELOG.md)
- [Commits](python-poetry/poetry-plugin-export@1.8.0...1.9.0)

---
updated-dependencies:
- dependency-name: poetry-plugin-export
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <[email protected]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

devtools/requirements-poetry.in

@@ -1,4 +1,4 @@
 # Fixing this here as readthedocs can't use the compiled requirements-poetry.txt
 # due to conflicts.
 poetry==2.0.0
-poetry-plugin-export==1.8.0
+poetry-plugin-export==1.9.0