sql: support partitioned hash sharded index

[cockroach-teamcity]

Exalate commented:

cockroachdb/cockroach#76358 --- Release note (sql change): Previously, crdb blocked users from creating hash sharded index in all kinds of partitioned tables including implict partitioned tables using PARTITION ALL BY or REGIONAL BY ROW. Now we turn on the support of hash sharded index in implicit partitioned tables. Which means primary key cannot be hash sharded if a table is explicitly partitioned with PARTITION BY or an index cannot be hash sharded if the index is explicitly partitioned with PARTITION BY. Paritioning columns cannot be placed explicitly as key columns of a hash sharded index as well, including regional-by-row table's crdb_region column.

Jira Issue: DOC-2711

[exalate-issue-sync]

Nick Vigilante (nickvigilante) commented:
[https://cockroachlabs.slack.com/archives/CARM0PTK4/p1644268878041489|https://cockroachlabs.slack.com/archives/CARM0PTK4/p1644268878041489|smart-card]

An implicitly partitioned table is a table that is partitioned with {{PARTITION ALL BY}} or {{REGIONAL BY ROW}}. An explicitly partitioned table is partitioned with {{PARTITION BY}}.