[FEATURE]Migrate Integrations to catalog

[YANG-DB]

Is your feature request related to a problem?

Migrate the integration content into the catalog

What solution would you like?

1. Create a designated folder for the integrations
2. Move the depended schema mapping away from the integrations and point to the catalog's existing schema folder
3. Add place holder for supporting ingestion pipelines in the integration

Do you have any additional context?

• [INTEGRATIONS-Tracking] Tracking Integrations Content dashboards-observability#668
• https://github.com/opensearch-project/dashboards-observability/tree/2.x/server/adaptors/integrations/__data__/repository
• [FEATURE]Allow loading integrations catalog from URL dashboards-observability#900
• [RFC] Integration RFC Definition And Spec dashboards-observability#644
• [RFC] Integration RFC Definition And Spec dashboards-observability#644
• https://github.com/opensearch-project/dashboards-observability/wiki/Integration-Creation-Guide

[YANG-DB]

done