Quotas: Some operations fail with a 255 volume type name

Fix proposed to branch: master
Review: https://review.opendev.org/c/openstack/cinder/+/815712

Reviewed: https://review.opendev.org/c/openstack/cinder/+/815712
Committed: https://opendev.org/openstack/cinder/commit/3a968212d6fc259f9f5855154a3e5246aa18eb10
Submitter: "Zuul (22348)"
Branch: master

commit 3a968212d6fc259f9f5855154a3e5246aa18eb10
Author: Gorka Eguileor <email address hidden>
Date: Wed Oct 27 18:46:53 2021 +0200

    DB: Set quota resource property length to 300

    On change I6c30a6be750f6b9ecff7399dbb0aea66cdc097da we increased the
    `resource` column of the quota_usages table from 255 to 300, because its
    value is constructed from (prefix + volume_type_name), but the length of
    `volume_type_name` can be up to 255 characters, so if we add a prefix
    such as 'volumes_' or 'gigabytes_' to it we'll exceed the db length
    limit of the `resource` column.

    There are other 3 quota related tables (quotas, quota_classes,
    reservations) that have a `resource` column, and they are all
    referencing the same kind of thing, but they still have a maximum size
    of 255 characters, so there will be things that we won't be able to do
    when using a volume type with a 255 characters name. Some of the
    operations we won't be able to do are setting a default quota limit for
    it or migrate volumes using that volume type.

    Related-Bug: #1798327
    Related-Bug: #1608849
    Closes-Bug: #1948962
    Change-Id: I40546b20322443dc34556de4aababf33a230db78

This issue was fixed in the openstack/cinder 24.0.0.0rc1 release candidate.