[POSTGRESQL] BREAKING CHANGE az postgres flexible-server upgrade: Remove the enum for --version

src/azure-cli/azure/cli/command_modules/postgresql/_breaking_change.py

@@ -22,12 +22,6 @@
                                  message='Long term retention command group will be removed. '
                                  'For more information, open a support incident.')
 
-# Upgrade command argument changes
-register_other_breaking_change('postgres flexible-server upgrade',
-                               message='The allowed values will be changed from set list to '
-                               'supported versions for upgrade based on capabilities.',
-                               arg='--version')
-
 # Name of new backup no longer required in backup create command
 register_other_breaking_change('postgres flexible-server backup create',
                                message='The argument for backup name will no longer be required '

src/azure-cli/azure/cli/command_modules/postgresql/_params.py

@@ -272,7 +272,6 @@ def _flexible_server_params(command_group):
         )
 
         pg_version_upgrade_arg_type = CLIArgumentType(
-            arg_type=get_enum_type(['13', '14', '15', '16', '17', '18']),
             options_list=['--version', '-v'],
             help='Server major version.'
         )