wc: move help strings to markdown file

[alexkunde]

#4368

wc --help now outputs the following:

./target/debug/coreutils wc --help
Display newline, word, and byte counts for each FILE, and a total line if
more than one FILE is specified. With no FILE, or when FILE is -, read standard input.

Usage: ./target/debug/coreutils wc [OPTION]... [FILE]...

Arguments:
  [files]...

Options:
  -c, --bytes            print the byte counts
  -m, --chars            print the character counts
      --files0-from <F>  read input from the files specified by
                             NUL-terminated names in file F;
                             If F is - then read names from standard input
  -l, --lines            print the newline counts
  -L, --max-line-length  print the length of the longest line
  -w, --words            print the word counts
  -h, --help             Print help information
  -V, --version          Print version information

[tertsdiepraam]

Thanks! I've approved the CI and left 2 small comments

[github-actions]

GNU testsuite comparison:

GNU test failed: tests/misc/timeout. tests/misc/timeout is passing on 'main'. Maybe you have to rebase?

[github-actions]

GNU testsuite comparison:

GNU test failed: tests/misc/timeout. tests/misc/timeout is passing on 'main'. Maybe you have to rebase?