[stubsabot] Bump pexpect to 4.9.*

[github-actions[bot]]

Release: https://pypi.org/pypi/pexpect/4.9.0 Homepage: https://pexpect.readthedocs.io/ Repository: https://github.com/pexpect/pexpect Diff: https://github.com/pexpect/pexpect/compare/4.8.0...4.9

Stubsabot analysis of the diff between the two releases:

• 4 public Python files have been added: examples/terminal_emulation.py, pexpect/socket_pexpect.py, tests/test_socket_fd.py, tests/test_socket_pexpect.py.
• 0 files included in typeshed's stubs have been deleted.
• 8 files included in typeshed's stubs have been modified or renamed.
• Total lines of Python code added: 1002.
• Total lines of Python code deleted: 451.

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