postgres hashdump now stores PostgresMD5 objects

instead of nonreplayabke hashes the postgres_hashdump
aux module now saves them approriately as PostgresMD5s
with the md5 tag intact at the front

MSP-12244

Author: David Maloney

modules/auxiliary/scanner/postgres/postgres_hashdump.rb

@@ -112,7 +112,7 @@ def run_host(ip)
         origin_type: :service,
         jtr_format: 'raw-md5,postgres',
         module_fullname: self.fullname,
-        private_type: :nonreplayable_hash
+        private_type: :postgres_md5
     }
 
     credential_data.merge!(service_data)
@@ -122,7 +122,6 @@ def run_host(ip)
       next if row[0].nil? or row[1].nil?
       next if row[0].empty? or row[1].empty?
       password = row[1]
-      password.slice!(0,3)
 
       credential_data[:username]     = row[0]
       credential_data[:private_data] = password