docs: Adding Azure Database for PostgreSQL docs (#25560)
This PR to show support for the Azure Database for PostgreSQL Vector
Store and Memory
[Azure Database for PostgreSQL - Flexible
Server](https://learn.microsoft.com/en-us/azure/postgresql/flexible-server/service-overview)
[Azure Database for PostgreSQL pgvector
extension](https://learn.microsoft.com/en-us/azure/postgresql/flexible-server/how-to-use-pgvector)
**Description:** Added vector store and memory usage documentation for
Azure Database for PostgreSQL
**Twitter handle:** [@_aiabe](https://x.com/_aiabe)
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Co-authored-by: Abeomor <{ID}+{username}@users.noreply.github.com>
