[improve][pulsar-function] Exposes pulsar producer schema in pulsar function context

[maxwell-cavnue]

Motivation

This PR exposes the ability to specify the schema type when using context.publish. We are running into errors with the default byte schema & the pulsar jdbc sink.

Our function needs to use context.publish as it sends to multiple topics.

Does this pull request potentially affect one of the following parts:

If the box was checked, please highlight the changes

• Dependencies (add or upgrade a dependency)
• The public API
• The schema
• The default values of configurations
• The threading model
• The binary protocol
• The REST endpoints
• The admin CLI options
• The metrics
• Anything that affects deployment

Documentation

• doc
• doc-required
• doc-not-needed
• doc-complete

Matching PR in forked repository

PR in forked repository:

[github-actions]

@maxwell-cavnue Please add the following content to your PR description and select a checkbox:

- [ ] `doc` <!-- Your PR contains doc changes -->
- [ ] `doc-required` <!-- Your PR changes impact docs and you will update later -->
- [ ] `doc-not-needed` <!-- Your PR changes do not impact docs -->
- [ ] `doc-complete` <!-- Docs have been already added -->

[jiangpengcheng]

@maxwell-cavnue thx for the contribution!

could u fork this repo and create the pr to your fork repo and make the CI passed first? after that, you can ask the community to run the CI workflows in this apache/pulsar repo

[maxwell-cavnue]

Guess this needs an update to https://github.com/apache/pulsar-client-python/blob/77fd33043614da87976e2c5230317b65104253a0/pulsar/functions/context.py#L139 as well?

[lhotari]

Guess this needs an update to https://github.com/apache/pulsar-client-python/blob/77fd33043614da87976e2c5230317b65104253a0/pulsar/functions/context.py#L139 as well?

@BewareMyPower Do you have an answer for this question?