Drupal 8 migrate: Using sub_process with entity_generate/entity_lookup: Looping through source field values and creating taxonomy terms for each of them.

migration.yml

# Looping through source field values and creating taxonomy terms for each of them (bundle_key and value_key are both required in this scenario)
field_name:
  -
    plugin: skip_on_empty
    method: process
    source: 'Source-Field-Name'
  -
    plugin: sub_process
    process:
      target_id:
        plugin: entity_generate
        bundle: vocabulary_id
        value_key: name
        bundle_key: vid
        source: 'Looping-Item-Property-Name'
        entity_type: taxonomy_term
        ignore_case: true