MDEV-30899: Fail to drop field CHECK constraint

[an3l]

• Patch allows to drop field check constraints using command that was previously used to drop table check constraints ALTER TABLE DROP CONSTRAINT [IF EXISTS] constraint_name

Reviewer: <>

Basing the PR against the correct MariaDB version

• [ ] This is a new feature and the PR is based against the latest MariaDB development branch.
• [ x] This is a bug fix and the PR is based against the earliest maintained branch in which the bug can be reproduced.

PR quality check

• [ x] I checked the CODING_STANDARDS.md file and my PR conforms to this where appropriate.
• [ x] For any trivial modifications to the PR, I am ok with the reviewer making the changes themselves.

[ailjushkin]

Thank you for your bugfix, could you please clarify what should be done to merge it? I'm facing this bug on 11.3.2-MariaDB-1:11.3.2+maria~ubu2204