This version forces prefixed binaries
(such as encrypted:TkQbjiVWtUJw3Ed/hkJ5JIsFIyhruKII6uKPXogfvDyMXGH1qQK3hVqshFolLN0S) to have alphanumeric prefixes ([a-zA-Z0-9_]+).

This allows us to tell a generated password value
with a colon from an tagged binary, for example:

# this is a not an encrypted value, or, in Cuttlefish speak,
# not a tagged one, so parse it has a "regular" password (binary)
default_password = 'abd:def07df783'

# this is an encrypted/tagged value,
# so parse it as a tagged tuple,
# {encrypted, <<"GhC4J5lh2DUkbdyKO0aMI8aYJ54mwe4eEWzou4yRFAHMF82IbD6cRiYAiBa8UIzR">>)
default_pass = encrypted:GhC4J5lh2DUkbdyKO0aMI8aYJ54mwe4eEWzou4yRFAHMF82IbD6cRiYAiBa8UIzR

If a value of, say, default_pass or ssl_options.password cannot be parsed as a tagged value, it will be parsed as a regular binary, because rabbit.schema
specifies multiple types as supported.

References #14233.