Remove broken generate-man option

[DanielNoord]

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Type of Changes

	Type
✓	🐛 Bug fix

Description

Turns out this was broken, probably for quite some time. Since nobody opened an issue about this and nobody seems to sue this anymore, I think this can be considered dead code. It wasn't tested anyway.
Closes #5283
Closes #1887

When you try to use this on main:

❯ pylint --generate-man
Traceback (most recent call last):
  File "/Users/daniel/.pyenv/versions/pylint-3.10.0/bin/pylint", line 33, in <module>
    sys.exit(load_entry_point('pylint', 'console_scripts', 'pylint')())
  File "/Users/daniel/DocumentenLaptop/Programming/Github/pylint/pylint/__init__.py", line 22, in run_pylint
    PylintRun(argv or sys.argv[1:])
  File "/Users/daniel/DocumentenLaptop/Programming/Github/pylint/pylint/lint/run.py", line 350, in __init__
    args = _config_initialization(
  File "/Users/daniel/DocumentenLaptop/Programming/Github/pylint/pylint/config/config_initialization.py", line 73, in _config_initialization
    parsed_args_list = linter.load_command_line_configuration(args_list)
  File "/Users/daniel/DocumentenLaptop/Programming/Github/pylint/pylint/config/option_manager_mixin.py", line 338, in load_command_line_configuration
    (options, args) = self.cmdline_parser.parse_args(args=args)
  File "/Users/daniel/.pyenv/versions/3.10.0/lib/python3.10/optparse.py", line 1387, in parse_args
    stop = self._process_args(largs, rargs, values)
  File "/Users/daniel/.pyenv/versions/3.10.0/lib/python3.10/optparse.py", line 1427, in _process_args
    self._process_long_opt(rargs, values)
  File "/Users/daniel/.pyenv/versions/3.10.0/lib/python3.10/optparse.py", line 1501, in _process_long_opt
    option.process(opt, value, values, self)
  File "/Users/daniel/DocumentenLaptop/Programming/Github/pylint/pylint/config/option.py", line 203, in process
    return self.take_action(self.action, self.dest, opt, value, values, parser)
  File "/Users/daniel/.pyenv/versions/3.10.0/lib/python3.10/optparse.py", line 805, in take_action
    self.callback(self, opt, value, parser, *args, **kwargs)
  File "/Users/daniel/DocumentenLaptop/Programming/Github/pylint/pylint/lint/run.py", line 442, in cb_generate_manpage
    self.linter.generate_manpage(__pkginfo__)
  File "/Users/daniel/DocumentenLaptop/Programming/Github/pylint/pylint/config/option_manager_mixin.py", line 230, in generate_manpage
    formatter.format_head(self.cmdline_parser, pkginfo, section),
  File "/Users/daniel/DocumentenLaptop/Programming/Github/pylint/pylint/config/man_help_formatter.py", line 46, in format_head
    short_desc = self.format_short_description(pgm, pkginfo.description)
AttributeError: module 'pylint.__pkginfo__' has no attribute 'description'

[coveralls]

Pull Request Test Coverage Report for Build 2081736358

• 1 of 1 (100.0%) changed or added relevant line in 1 file are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+0.3%) to 94.537%

---

Totals
Change from base Build 2081637560:	0.3%
Covered Lines:	15505
Relevant Lines:	16401

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💛 - Coveralls

[Pierre-Sassoulas]

I really like removing unused code.