Update Transform spec from upstream elasticsearch-specification

[andrewkroh]

The missing num_failure_retries has been added to the Elasticsearch specification for the Transform API. We should sync the package-spec definition with the upstream definition to add the new parameter.

package-spec/spec/integration/elasticsearch/transform/transform.spec.yml

Lines 151 to 190 in 1fb1dd6

	settings:
	"$id": "#root/settings"
	title: Settings
	type: object
	additionalProperties: false
	properties:
	dates_as_epoch_millis:
	"$id": "#root/settings/dates_as_epoch_millis"
	title: Dates as epoch millis
	type: boolean
	default: false
	docs_per_second:
	"$id": "#root/settings/docs_per_second"
	title: docs per second
	type: number
	align_checkpoints:
	"$id": "#root/settings/align_checkpoints"
	title: align checkpoints
	type: boolean
	default: true
	max_page_search_size:
	"$id": "#root/settings/max_page_search_size"
	title: max page search size
	type: integer
	default: 500
	use_point_in_time:
	"$id": "#root/settings/use_point_in_time"
	title: use_point_in_time
	type: boolean
	default: true
	deduce_mappings:
	"$id": "#root/settings/deduce_mappings"
	title: deduce mappings
	type: boolean
	default: true
	unattended:
	"$id": "#root/settings/unattended"
	title: unattended
	type: boolean
	default: false

Relates: elastic/elasticsearch-specification#5801