Fix parsing of query field of RowsQueryEvent

[dongwook-chan]

Description

The first byte of payload in RowsQueryEvent must be ignored without being used as the length for the following field query. Yet, the existing code did use this value as length for query and fails whenever parsing query longer than 255 characters which is the maximum value that a single byte can hold.

I fixed the bug referring to code from msql-server.

Other clients in different languages implement the RowsQueryEvent the way mysql-server does and noted below as references.

• MysqlCdc (c#)
• mysql-binlog-connector-java (java)

Type of Change

• [x] Bug fix
• [ ] New feature
• [ ] Documentation update
• [ ] Other (please specify below)

Checklist

• [x] I have read and understood the CONTRIBUTING.md document.
• [x] I have checked there aren't any other open Pull Requests for the desired changes.
• [x] This PR resolves an issue #601.

Tests

• [x] All tests have passed.
• [x] New tests have been added to cover the changes. (describe below if applicable).

Additional Information

[avaitla]

This also crashes for our MySQL 8.035. Would love to see it merged in. We are having to use: poetry add git+ssh://git@github.com:dongwook-chan/python-mysql-replication.git