"$" character not recognised by the 'm, --method | TYPE' option

_mkpasswd v. 5.6.6_

```
MKPASSWD(1)

 -m TYPE, --method=TYPE
  [...] If TYPE begins and end with $ characters then the string is passed to crypt_gensalt(3) as-is.
```
_note_: missing "s" in "end", if meant to be "ends".

```
$ mkpasswd -m $yescrypt$
Invalid method '$'.
```
Should be effective.