Add support for mutating an Iceberg branch

[tdcmeehan]

Iceberg supports mutations (upserts, deletes, inserts) on branches. We should allow Presto to specify a branch during mutations so that users can, e.g., perform experiments on data without having to copy the data elsewhere.

Part of #22025

Expected Behavior or Use Case

INSERT INTO iceberg.default.table AT BRANCH 'my-branch' VALUES ...

Presto Component, Service, or Connector

Presto Iceberg connector, and some changes to the parser and SPI to allow a branch to be specified.

Possible Implementation

Example Screenshots (if appropriate):

Context

Hive syntax: https://medium.com/@ayushtkn/apache-hive-4-x-with-iceberg-branches-tags-3d52293ac0bf
Spark syntax: https://iceberg.apache.org/docs/latest/branching/#audit-branch