MySQL/MariaDB insert fails for datetime_with_timezone columns – generates invalid timestamp with time zone literal

### Version Information

Server Version:
2.38.1

### Environment

EE

### What is the current behaviour?

When inserting into a MariaDB table with TIMESTAMP columns tracked in Hasura, Hasura exposes those columns as the GraphQL scalar datetime_with_timezone.

When executing an insert_* mutation against those columns, the MySQL/MariaDB connector generates SQL that includes a PostgreSQL-style literal cast:

timestamp with time zone '2025-08-14 14:59:45+00:00'

This syntax is not valid in MySQL/MariaDB, resulting in a syntax error.

Error returned:

```
You have an error in your SQL syntax; check the manual that corresponds to your MariaDB server version for the right syntax to use near 'with time zone '2025-08-14 14:59:45+00:00'..."
```

Impact: Any MySQL/MariaDB table with TIMESTAMP columns mapped as datetime_with_timezone cannot be inserted into via the generated mutations.

### What is the expected behaviour?

Inserts work as expected

### How to reproduce the issue?

1. Create table in mariadb with timestamp column
2.Track table
3. Graphql schema for timestamp column is typed as datetime_with_timezone
4. Run mutation for example:
```
mutation insert {
insert_test_table(objects: {start_time: "2025-01-02T12:01:02+00:00", id: 10, end_time: "2025-01-02T12:01:02+00:00", user_id: "23232"}) {
affected_rows
}
}

}
```

### Screenshots or Screencast

### Please provide any traces or logs that could help here.

### Any possible solutions/workarounds you're aware of?

Use DATETIME column type instead, and graphql schema generates a datetime type

### Keywords

Start with the MySQL/MariaDB connector path that builds SQL for insert mutations and handles the datetime_with_timezone scalar. Reproduce the issue using the MariaDB TIMESTAMP table and mutation described here, then verify that the generated insert uses syntax accepted by MySQL/MariaDB and completes successfully.

Written by the indexing model from the issue text.