[DocDB] PITR: Disallow TRUNCATE

[bmatican]

Description

Since TRUNCATE is not transactional and we do not yet have #7130, we should just disable TRUNCATE being executed against tables involved in PITR.

The work is likely to be similar to #8415.

[bmatican]

Docs for trying out PITR: https://docs.yugabyte.com/latest/explore/cluster-management/point-in-time-recovery-ysql/

For the master side work, we'll probably need the same type of glue in CatalogManager::TruncateTable.

Feel free to reach out to @sanketkedia for more info on PITR.

Note: As per @frozenspider and @jaki , we'll need to also factor in, for all of these TRUNCATE paths, that colocation is a tserver-side DDL operation. Context: https://yugabyte.slack.com/archives/CAR5BCH29/p1647556951578069

However, would also be interesting to investigate, perhaps in a test, what happens if we send the master a TruncateTable RPC, for a colocated table? The code looks as if it warns, but then continues?

 4586   // Truncate on a colocated table should not hit master because it should be handled by a write
 4587   // DML that creates a table-level tombstone.
 4588   LOG_IF(WARNING, table->IsColocatedUserTable()) << "cannot truncate a colocated table on master";
...
 4597   // Send a Truncate() request to each tablet in the table.
 4598   SendTruncateTableRequest(table);