ykman 5.4.0 crashes on fido set-min-length when FIDO PIN is not supported

[disconnect3d]

• YubiKey Manager (ykman) version: 5.4.0
• How was it installed?: installed from Homebrew (Homebrew formula)
• Operating system and version: macOS Sonoma 14.2
• YubiKey model and version: Yubikey 5C Nano, firmware 4.3.7
• Bug description summary: the ykman fido access set-min-length 4 crashes

Steps to reproduce

$ ykman --version
YubiKey Manager (ykman) version: 5.4.0

$ ykman info
Device type: YubiKey 4
Serial number: <redacted>
Firmware version: 4.3.7
Enabled USB interfaces: OTP, FIDO, CCID

Applications
Yubico OTP  	Enabled
FIDO U2F    	Enabled
FIDO2       	Not available
OATH        	Enabled
PIV         	Enabled
OpenPGP     	Enabled
YubiHSM Auth	Not available

$ ykman fido access set-min-length 4
ERROR: An unexpected error has occurredTraceback (most recent call last):
  File "/usr/local/Cellar/ykman/5.4.0/libexec/lib/python3.12/site-packages/ykman/_cli/__main__.py", line 421, in main
    cli(obj={})
  File "/usr/local/Cellar/ykman/5.4.0/libexec/lib/python3.12/site-packages/click/core.py", line 1157, in __call__
    return self.main(*args, **kwargs)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/local/Cellar/ykman/5.4.0/libexec/lib/python3.12/site-packages/click/core.py", line 1078, in main
    rv = self.invoke(ctx)
         ^^^^^^^^^^^^^^^^
  File "/usr/local/Cellar/ykman/5.4.0/libexec/lib/python3.12/site-packages/click/core.py", line 1688, in invoke
    return _process_result(sub_ctx.command.invoke(sub_ctx))
                           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/local/Cellar/ykman/5.4.0/libexec/lib/python3.12/site-packages/click/core.py", line 1688, in invoke
    return _process_result(sub_ctx.command.invoke(sub_ctx))
                           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/local/Cellar/ykman/5.4.0/libexec/lib/python3.12/site-packages/click/core.py", line 1688, in invoke
    return _process_result(sub_ctx.command.invoke(sub_ctx))
                           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/local/Cellar/ykman/5.4.0/libexec/lib/python3.12/site-packages/click/core.py", line 1434, in invoke
    return ctx.invoke(self.callback, **ctx.params)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/local/Cellar/ykman/5.4.0/libexec/lib/python3.12/site-packages/click/core.py", line 783, in invoke
    return __callback(*args, **kwargs)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/local/Cellar/ykman/5.4.0/libexec/lib/python3.12/site-packages/click/decorators.py", line 33, in new_func
    return f(get_current_context(), *args, **kwargs)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/local/Cellar/ykman/5.4.0/libexec/lib/python3.12/site-packages/ykman/_cli/fido.py", line 525, in set_min_pin_length
    info = ctx.obj["ctap2"].info
           ~~~~~~~^^^^^^^^^
  File "/usr/local/Cellar/ykman/5.4.0/libexec/lib/python3.12/site-packages/ykman/_cli/util.py", line 198, in __getitem__
    return self._objects[key]
           ~~~~~~~~~~~~~^^^^^
KeyError: 'ctap2'

Expected result

Since this firmware version does not support FIDO PIN, setting min length for it does not make sense.

I expected a similar error as here:

$ ykman fido access verify-pin
ERROR: This YubiKey does not support a FIDO PIN.

[dainnilsson]

This is resolved in the latest version (5.5.0)