fix: Better error message for CREATE SOURCE without connector

[gengteng]

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What's changed and what's your intention?

resolve #8792

Improve error message when 'connector' or 'WITH' clause is missing from a CREATE SOURCE statement.

Checklist For Contributors

• I have written necessary rustdoc comments
• I have added necessary unit tests and integration tests
• I have added fuzzing tests or opened an issue to track them. (Optional, recommended for new SQL features Sqlsmith: Sql feature generation #7934).
• I have demonstrated that backward compatibility is not broken by breaking changes and created issues to track deprecated features to be removed in the future. (Please refer to the issue)
• All checks passed in ./risedev check (or alias, ./risedev c)

Checklist For Reviewers

• I have requested macro/micro-benchmarks as this PR can affect performance substantially, and the results are shown.

Documentation

Error Message

If the 'connector' field is missing from a CEATE SOURCE statement, the user will get an error message:

Protocol error: missing field 'connector'

If the 'WITH' clause is missing from a CREATE SOURCE statement, he or she will get an error message:

Invalid input syntax: missing WITH clause

[xxchan]

LGTM. Thanks!

[xxchan]

One little hint on GitHub (I've changed that): This syntax can close related issue automatically 😄

[gengteng]

One little hint on GitHub (I've changed that): This syntax can close related issue automatically 😄

Thank you for the reminder. I'll use this syntax when submitting future PRs. 😄

[xxchan]

There are compile error after merging main. Please update branch and fix that 🙏