feat: allow other password hashing algorithms

[juanpicado]

Same as #1917 but in v.5.x.x
and crypt enable by default to avoid breaking changes.

Enable more algorithms for hasing password only for htpasswd plugin, crypt by default to avoid breaking changes but bcrypt recommended.

auth:
  htpasswd:
    file: ./htpasswd
    # Maximum amount of users allowed to register, defaults to "+inf".
    # You can set this to -1 to disable registration.
    # max_users: 1000
    # Hash algorithm, possible options are: "bcrypt", "md5", "sha1", "crypt".
    algorithm: bcrypt # by default is crypt, but is recommended use bcrypt for new installations
    # Rounds number for "bcrypt", will be ignored for other algorithms.
    rounds: 10

ref verdaccio/monorepo#580