Allow reflecting UUID in MariaDB

Allow reflecting UUID in MariaDB

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### Description
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Added the `"uuid"` key to `ischema_names` to enable lookup of `UUID` columns in reflection. There's also a new short test (MariaDB 10.7+ only) in the mysql reflection tests to verify if this feature works correctly.

Fixes #10028

### Checklist
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This pull request is:

- [ ] A documentation / typographical error fix
	- Good to go, no issue or tests are needed
- [x] A short code fix
	- please include the issue number, and create an issue if none exists, which
	  must include a complete example of the issue.  one line code fixes without an
	  issue and demonstration will not be accepted.
	- Please include: `Fixes: #<issue number>` in the commit message
	- please include tests.   one line code fixes without tests will not be accepted.
- [ ] A new feature implementation
	- please include the issue number, and create an issue if none exists, which must
	  include a complete example of how the feature would look.
	- Please include: `Fixes: #<issue number>` in the commit message
	- please include tests.

**Have a nice day!**

Closes: #10029
Pull-request: https://github.com/sqlalchemy/sqlalchemy/pull/10029
Pull-request-sha: 7c2838b1dd5a34166158f5e241af72a6d3d8be85

Change-Id: Ifa1f51f472809b35374a7e2c6b85412046133452