Bump pexpect from 4.8.0 to 4.9.0

Bumps [pexpect](https://github.com/pexpect/pexpect) from 4.8.0 to 4.9.0.
- [Release notes](https://github.com/pexpect/pexpect/releases)
- [Changelog](https://github.com/pexpect/pexpect/blob/master/doc/history.rst)
- [Commits](pexpect/pexpect@4.8.0...4.9)

---
updated-dependencies:
- dependency-name: pexpect
  dependency-type: indirect
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <[email protected]>

requirements/dev-requirements.txt

@@ -128,7 +128,7 @@ parso==0.8.3
     # via jedi
 pathspec==0.12.1
     # via black
-pexpect==4.8.0
+pexpect==4.9.0
     # via ipython
 pickleshare==0.7.5
     # via ipython