Bump pexpect to 4.9

[tapple]

The only api change is the addition of SocketSpawn, which I also contributed: pexpect/pexpect#745

I also fixed some Incomplete typings while I was at it

[tapple]

@fperrin I addressed your comments

[github-actions]

Diff from mypy_primer, showing the effect of this PR on open source code:

pytest (https://github.com/pytest-dev/pytest)
+ src/_pytest/pytester.py:1503: error: Missing type parameters for generic type "spawn"  [type-arg]
+ src/_pytest/pytester.py:1517: error: Missing type parameters for generic type "spawn"  [type-arg]
- src/_pytest/pytester.py:1531: error: Returning Any from function declared to return "spawn"  [no-any-return]
+ src/_pytest/pytester.py:1531: error: Returning Any from function declared to return "spawn[Any]"  [no-any-return]
+ src/_pytest/legacypath.py:257: error: Missing type parameters for generic type "spawn"  [type-arg]
+ src/_pytest/legacypath.py:261: error: Missing type parameters for generic type "spawn"  [type-arg]
+ testing/test_debugging.py:255: error: Item "None" of "Any | None" has no attribute "decode"  [union-attr]
+ testing/test_debugging.py:292: error: Item "None" of "Any | None" has no attribute "decode"  [union-attr]
+ testing/test_debugging.py:350: error: Item "None" of "Any | None" has no attribute "decode"  [union-attr]
+ testing/test_debugging.py:415: error: Item "None" of "Any | None" has no attribute "decode"  [union-attr]
+ testing/test_debugging.py:511: error: Item "None" of "Any | None" has no attribute "decode"  [union-attr]
+ testing/test_debugging.py:515: error: Item "None" of "Any | None" has no attribute "decode"  [union-attr]
+ testing/test_debugging.py:636: error: Unsupported right operand type for in ("Any | None")  [operator]
+ testing/test_debugging.py:638: error: Item "None" of "Any | None" has no attribute "endswith"  [union-attr]
+ testing/test_debugging.py:644: error: Unsupported right operand type for in ("Any | None")  [operator]
+ testing/test_debugging.py:645: error: Unsupported right operand type for in ("Any | None")  [operator]
+ testing/test_debugging.py:738: error: Item "None" of "Any | None" has no attribute "decode"  [union-attr]
+ testing/test_debugging.py:745: error: Item "None" of "Any | None" has no attribute "decode"  [union-attr]
+ testing/test_debugging.py:751: error: Item "None" of "Any | None" has no attribute "decode"  [union-attr]
+ testing/test_debugging.py:756: error: Item "None" of "Any | None" has no attribute "decode"  [union-attr]
+ testing/test_debugging.py:1075: error: Item "None" of "Any | None" has no attribute "decode"  [union-attr]
+ testing/test_debugging.py:1122: error: Item "None" of "Any | None" has no attribute "decode"  [union-attr]
+ testing/test_debugging.py:1211: error: Item "None" of "Any | None" has no attribute "decode"  [union-attr]
+ testing/test_debugging.py:1220: error: Item "None" of "Any | None" has no attribute "decode"  [union-attr]

core (https://github.com/home-assistant/core)
+ homeassistant/components/aruba/device_tracker.py:127: error: Item "None" of "str | None" has no attribute "split"  [union-attr]
+ homeassistant/components/aruba/device_tracker.py:127: error: No overload variant of "split" of "str" matches argument type "bytes"  [call-overload]
+ homeassistant/components/aruba/device_tracker.py:127: note: Possible overload variants:
+ homeassistant/components/aruba/device_tracker.py:127: note:     def split(self, sep: str | None = ..., maxsplit: SupportsIndex = ...) -> list[str]

[fperrin]

@fperrin I addressed your comments

Thanks! I'm happy with the changes in fdexpect 👍

I only use a small portion of pexpect, so I am not qualified to comment on the rest of the changes.

[hauntsaninja]

Thank you!