PR #91205 - descidgen: use system.descriptor_id_seq for all tenants

[cockroach-teamcity]

Exalate commented:

Related PR: https://github.com/cockroachdb/cockroach/pull/91205 Commit: https://github.com/cockroachdb/cockroach/commit/c46c1975f62289825af7c5096d1ea860a79f4c31

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Release note (sql change): upgrading a cluster to a major release containing this patch will endow the system tenant's system database with a descriptor_id_seq sequence which will henceforth be used to generate new descriptor IDs, as is already the case for non-system tenants.

Jira Issue: DOC-6134