feat(alloydb): add new PSC instance configuration setting and output …

…the PSC DNS name (#11015)

- [ ] Regenerate this pull request now.

feat(alloydb): add new API to execute SQL statements
feat(alloydb): add support for Free Trials
feat(alloydb): add support to schedule maintenance
feat(alloydb): additional field to set tags on a backup or cluster
feat(alloydb): add more observability options on the Instance level
feat(alloydb): add new API to perform a promotion or switchover on secondary instances
feat(alloydb): support for obtaining the public ip addresses of an instance and enabling either inbound or outbound public ip
feat(alloydb): add new API to list the databases in a project and location
feat(alloydb): add optional field to keep extra roles on a user if it already exists
docs(alloydb): various typo fixes, correcting the formatting, and clarifications on the request_id and validate_only fields in API requests and on the page_size when listing the database

PiperOrigin-RevId: 688544999

Source-Link: https://togithub.com/googleapis/googleapis/commit/113ddfebbe8d4e0639eb19fe91817a13edfc0c5c

Source-Link: https://togithub.com/googleapis/googleapis-gen/commit/14fa50edd57629ab318bb7b98a7286b46749e8df
Copy-Tag: eyJwIjoiLmdpdGh1Yi8uT3dsQm90LnlhbWwiLCJoIjoiMTRmYTUwZWRkNTc2MjlhYjMxOGJiN2I5OGE3Mjg2YjQ2NzQ5ZThkZiJ9