Migrate yandex connection UI metadata to YAML

[fat-catTW]

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Description

Updated providers/yandex/provider.yaml for connection type yandexcloud

Changes

Added ui-field-behaviour.hidden-fields to hide default connection fields (host, schema, login, password, port, extra)
Added conn-fields definitions for:
service_account_json
service_account_json_path
oauth
older_id
public_ssh_key
endpoint

Regenerated providers/yandex/src/airflow/providers/yandex/get_provider_info.py so the runtime provider info reflects the YAML changes.

related: #62345

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